Pronunciation: /əˈbɔːtɪv ˌpəʊliəʊˌmaɪəˈlaɪtɪs/ · Part of speech: noun · Field: infectious disease / virology

Definition. Abortive poliomyelitis is a mild form of polio that affects only the throat and intestines, without involving the central nervous system. The name reflects the sense of abortive meaning “cut short” or “not running its full course” — the infection does not progress to the more serious, paralytic stages of the disease.

Where it fits among the forms of polio. Poliomyelitis, caused by the poliovirus, can present in several forms of differing severity:

• Asymptomatic (subclinical) infection — the most common outcome, in which the person has no symptoms at all.
• Abortive poliomyelitis — a mild, non-specific illness, the subject of this entry.
• Non-paralytic poliomyelitis — a more pronounced illness that may include signs of meningeal irritation (such as neck stiffness) but no lasting paralysis.
• Paralytic poliomyelitis — the most serious form, in which the virus damages motor nerve cells and causes muscle weakness or paralysis.

Abortive poliomyelitis represents the milder end of the symptomatic spectrum.

Typical features. Because the infection in this form is limited to the throat and gut rather than the nervous system, its symptoms are generally non-specific and resemble those of many minor viral illnesses: sore throat, fever, general malaise, loss of appetite, nausea, vomiting, abdominal discomfort, and sometimes headache. The illness is usually short-lived, and recovery is typically complete, without the neurological involvement seen in the more severe forms. Because the symptoms are so non-specific, abortive poliomyelitis is often not recognised as polio unless it occurs in a known outbreak.

Clinical and public-health relevance. Although mild for the affected individual, even non-paralytic and abortive infections matter from a public-health standpoint, because infected people can still shed the virus and transmit it to others, some of whom may go on to develop the paralytic form. This is one reason that widespread vaccination, which has dramatically reduced polio worldwide, remains so important.

Distinction from related terms. Paralytic poliomyelitis is the severe, nerve-damaging form. Non-paralytic poliomyelitis involves the nervous system without causing paralysis. Post-polio syndrome refers to new symptoms appearing years after recovery from paralytic polio. Abortive poliomyelitis is distinguished by being limited to the throat and intestines, with no nervous-system involvement.

Etymology. Abortive from Latin aboriri, “to fail to come to fruition” (here meaning the infection is cut short); poliomyelitis from Greek polios (“grey”) + myelos (“marrow,” referring to the spinal cord) + -itis (“inflammation”) — literally, inflammation of the grey matter of the spinal cord.

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional regarding any clinical questions.

Pronunciation: /əˈbɔːtɪv/ · Part of speech: adjective · Field: general English with specific medical uses

Definition. In its everyday sense, abortive means not successful — failing to achieve its intended result, as in an abortive attempt (an effort that does not succeed or is broken off before completion). The core idea is of something cut short or coming to nothing before it reaches its goal.

General use. Used in ordinary language, “abortive” describes plans, efforts, or actions that fail or are abandoned partway: an abortive attempt to escape, an abortive negotiation, an abortive coup. In each case the action began but did not reach a successful conclusion.

Medical uses. Within medicine, abortive carries two related but more specific meanings:

• Halting a process early. An abortive treatment or abortive therapy is one given to stop a condition before it fully develops or runs its course. For example, abortive treatment of a migraine aims to stop an attack once symptoms begin, as opposed to preventive (prophylactic) treatment, which aims to stop attacks from starting in the first place.
• Incomplete development. “Abortive” can describe a structure or process that is incompletely formed or arrested in its development — for instance, an abortive organ that has not developed fully, or an abortive infection, in which a virus enters cells but the full infectious process does not complete.

Connecting the senses. All of these uses share the same underlying notion found in the word abort: something that is stopped, broken off, or fails to reach full completion. Whether describing a failed attempt, a treatment that halts a condition early, or a structure that did not develop fully, “abortive” points to incompleteness or non-fulfilment.

Distinction from related terms. Unsuccessful and failed are general synonyms for the everyday sense. Prophylactic (preventive) contrasts with the medical sense of abortive treatment, since prophylaxis prevents a process from starting while abortive therapy stops one already begun. Rudimentary or vestigial describe incompletely or under-developed structures and overlap with one medical meaning of “abortive.”

Etymology. From Latin abortivus, from aboriri, “to miscarry” or “to fail to be born” (ab- = away, amiss + oriri = to arise, to be born) — literally, pertaining to that which fails to come to fruition.

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional regarding any clinical questions.

Pronunciation: /əˈbɔːʃ(ə)n ˈtrɔːmə ˈsɪndrəʊm/ · Part of speech: noun · Field: psychology / mental health

Definition (as given). Abortion trauma syndrome is described as a set of symptoms sometimes experienced in the period after an abortion, said to include guilt, anxiety, depression, low self-esteem, disturbances of eating and sleeping, and suicidal thoughts. The term groups these reported experiences under a single label as a supposed reaction following the procedure.

Important note on scientific status. This is an area where accuracy matters, so a key point must be added to the dictionary definition: “abortion trauma syndrome” is not a recognised clinical diagnosis. It does not appear in the major diagnostic classification systems (such as the DSM or ICD), and major professional bodies — including organisations representing psychologists and psychiatrists — have concluded that the available high-quality evidence does not support the existence of a distinct syndrome caused by abortion. The term originated largely in advocacy contexts rather than in mainstream clinical research, and it remains contested. For these reasons it should be understood as a proposed or disputed concept, not an established medical condition.

What the evidence broadly indicates. Research on this question is methodologically difficult, and findings must be read with care. In general terms, large reviews suggest that most people do not experience lasting severe psychological harm attributable to abortion itself, and that the strongest predictors of distress afterwards tend to be a person’s pre-existing mental health, the circumstances surrounding the pregnancy, and the level of social support available — rather than the procedure acting as a unique cause. This does not mean no one ever experiences difficult emotions afterwards; people can and do have a wide range of feelings, and those feelings are real and valid regardless of how the syndrome label is judged scientifically.

Why the distinction matters. Whether a cluster of symptoms is recognised as a genuine, distinct syndrome affects how it is researched, discussed, and addressed clinically. Describing emotional difficulties accurately — without either dismissing real distress or attributing it to a condition that mainstream science does not recognise — allows people to receive appropriate, evidence-based support.

Related terminology. Post-traumatic stress disorder (PTSD) is a recognised diagnosis with specific criteria. Perinatal or postnatal depression are recognised mood conditions linked to pregnancy and childbirth. Grief describes a normal emotional response to loss. These are distinct, established concepts, whereas “abortion trauma syndrome” is not among them.

Etymology. A compound of abortion (Latin aboriri, “to miscarry”), trauma (Greek trauma, “wound”), and syndrome (Greek syndrome, “a running together,” meaning a set of symptoms that occur together).

If you or someone you know is affected by difficult feelings after a pregnancy loss or abortion, including the kinds of distress listed above, support is available, and a doctor, counsellor, or mental health professional can help. I’m also happy to help you find appropriate resources if that would be useful.

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment, and it does not advocate any particular position on a contested topic. Always consult a qualified healthcare or mental health professional regarding any clinical or personal questions.

Pronunciation: /əˈbɔːʃ(ə)n pɪl/ · Part of speech: noun · Field: obstetrics / pharmacology

Definition. The abortion pill is a common, everyday name for a drug (or, more accurately, a regimen of medication) that causes an abortion to occur very early in pregnancy. It refers to medical abortion — ending a pregnancy with medication rather than with a surgical procedure.

What it refers to. In ordinary use, “the abortion pill” usually describes a medication-based method used in the early weeks of pregnancy. Medical abortion typically involves medicines that work in two complementary ways: one type interrupts the hormonal support a pregnancy needs to continue, and another stimulates the uterus to contract and empty. Because this is a sensitive medical topic, the specific drugs, doses, timing, and gestational limits are determined by clinicians and regulated differently in each country; the description here is general rather than a set of instructions.

Distinction from emergency contraception. A very common and important point of confusion is the difference between the abortion pill and the morning-after pill (emergency contraception). They are not the same:

• Emergency contraception is taken after unprotected sex to help prevent a pregnancy from becoming established. It works before pregnancy is confirmed and does not end an established pregnancy.
• The abortion pill is used to end a pregnancy that has already begun.

Confusing the two can lead to misunderstanding about how and when each is used.

Clinical and safety relevance. Medical abortion is used within defined limits of gestational age and requires medical assessment, supervision, and follow-up to confirm that the process is complete and to manage any complications, such as heavy bleeding or incomplete abortion. Its legal availability and the conditions for its use vary considerably between countries and regions. Because of these medical and legal complexities, decisions and any use of such medication are made with a qualified healthcare professional and within the applicable legal framework.

Related terminology. Medical abortion is the clinical term for using medication to end a pregnancy, as opposed to surgical abortion. An abortifacient is the general term for any drug or instrument that provokes an abortion. To abort is the verb, and abortion names the event or procedure.

Etymology. A compound of abortion (Latin abortio, from aboriri, “to miscarry”) and pill (from Latin pilula, “little ball”), used informally to name a medication that brings about abortion.

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment, and it does not provide instructions for any procedure or advocate any course of action. Always consult a qualified healthcare professional regarding any clinical questions, and be aware that laws and regulations on this subject vary by location.

Pronunciation: /əˈbɔːʃ(ə)nɪst/ · Part of speech: noun · Field: medicine / legal-historical

Definition. An abortionist is a person who helps a woman to abort — that is, someone who performs or assists in ending a pregnancy. In practice the word is most often used to refer specifically to a person who performs an illegal abortion, and it usually carries a negative or disapproving tone.

Connotation and usage. This is an important point about the word: although it can literally describe anyone who carries out an abortion, in ordinary usage abortionist tends to imply that the procedure is performed outside the law, or by someone who is unqualified or operating in unsafe conditions. For this reason it is generally regarded as a pejorative term and is not the neutral way to describe a qualified clinician. In contemporary medical and respectful usage, a doctor or healthcare professional who lawfully carries out the procedure is referred to by their professional title (for example, a doctor, physician, gynaecologist, or abortion provider) rather than as an “abortionist.”

Historical and public-health context. The term is closely tied to the history of illegal or “back-street” abortion — procedures carried out before legalisation or outside legal frameworks, often without proper medical training, sterile conditions, or follow-up care. Such circumstances were associated with serious risks to the woman, including severe bleeding, infection, injury, and death. The recognition of these dangers was a major factor in public-health and legal debates that led many countries to regulate the procedure within the medical system.

Safety and legal relevance. The distinction the definition draws — between lawful, medically supervised procedures and illegal ones — matters greatly for safety. Abortions carried out by unqualified people or in unsanitary conditions carry substantially higher risks than those performed lawfully within a healthcare system. Laws governing who may perform the procedure, and under what circumstances, vary widely between jurisdictions.

Distinction from related terms. Abortion is the event or procedure itself; to abort is the verb; an abortifacient is a drug or instrument that provokes an abortion; and an abortion provider is a more neutral modern term for a clinician who lawfully performs the procedure. Abortionist differs from these in that it specifically denotes a person who carries out the procedure and usually implies an illegal or unqualified context.

Etymology. From abortion (Latin abortio, from aboriri, “to miscarry”) combined with the suffix -ist, denoting a person who does or practises something.

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment, and it does not advocate any particular course of action. Always consult a qualified healthcare professional regarding any clinical questions, and be aware that laws and regulations on this subject vary by location.

Pronunciation: /əˈbɔːʃ(ə)n/ · Part of speech: noun · Verb form: to abort · Field: obstetrics / general medicine

Definition. An abortion is a situation in which a fetus leaves the uterus before it is fully developed — especially during the first 28 weeks of pregnancy — or a procedure that causes this to happen. To have an abortion means to undergo an operation or treatment that ends the pregnancy during its earlier stages.

Spontaneous versus induced. Medically, the word covers two broad situations:

• Spontaneous abortion — the pregnancy ends naturally, without intervention. In everyday language this is called a miscarriage.
• Induced abortion — the pregnancy is deliberately ended by medical (drug-based) or surgical means.

In both senses, the defining feature is that the fetus leaves the uterus before it is fully developed.

Clinical subtypes. In medical terminology, several specific terms describe particular situations:

• Threatened abortion — bleeding occurs in early pregnancy but the pregnancy may still continue.
• Inevitable abortion — the process has begun and cannot be stopped.
• Incomplete abortion — only part of the pregnancy’s contents has been expelled.
• Complete abortion — all the contents have been expelled.
• Missed abortion — the fetus has died but has not yet been expelled.
• Recurrent (habitual) abortion — repeated spontaneous losses across successive pregnancies.

Legal context (as noted for the UK). As the accompanying comment indicates, abortion is regulated by law, and the rules differ from country to country. In the UK, an abortion can be carried out legally if two doctors agree that continuing the pregnancy poses a risk to the mother’s life, that it risks grave permanent injury to her physical or mental health or that of her existing children, or that the fetus is likely to be born with severe disabilities. Legal frameworks elsewhere may be more or less restrictive, so the lawful basis for the procedure always depends on local legislation.

Clinical relevance. Abortion — whether spontaneous or induced — is a significant event with medical, emotional, ethical, and legal dimensions. Care involves assessing the woman’s health, managing any complications such as bleeding or infection, and providing appropriate support. Because of the personal and legal complexity of the subject, decisions are made individually, within the applicable legal framework and with professional guidance.

Distinction from related terms. Miscarriage is the lay term for spontaneous abortion. Stillbirth refers to fetal death at a later stage, after the threshold of viability, and is distinct from abortion. Premature birth means the delivery of a live infant before full term. “Abortion” specifically denotes the loss or ending of a pregnancy before the fetus is fully developed.

Etymology. From Latin abortio, from aboriri, “to miscarry” or “to fail to be born” (ab- = away, amiss + oriri = to be born, to arise).

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment, and it does not advocate any particular course of action. Always consult a qualified healthcare professional regarding any clinical questions, and be aware that laws and regulations on this subject vary by location.

Pronunciation: /əˌbɔːtɪˈfeɪʃ(ə)nt/ · Part of speech: noun (also used as an adjective) · Field: obstetrics / pharmacology

Definition. An abortifacient is a drug or instrument that provokes an abortion — that is, an agent or device used to bring about the ending of a pregnancy before the fetus is fully developed. The word can also function as an adjective describing something that has this effect (an abortifacient agent).

Two broad types. The dictionary definition reflects that an abortifacient may be either pharmacological or mechanical:

• Drugs — substances that act on the body, for example by altering the hormones that maintain pregnancy or by causing the uterus to contract and expel its contents.
• Instruments — physical devices or surgical tools used to end a pregnancy.

In both cases, the defining feature is the capacity to provoke an abortion.

How drug abortifacients work (in general terms). Pharmacological abortifacients typically act through one of a few mechanisms: interfering with the hormonal support a pregnancy depends on, or stimulating contraction of the uterine muscle so that the uterus empties. The specific medicines, their use, and their regulation vary considerably by country and clinical context, and they are administered only under appropriate medical and legal frameworks.

Related terminology. The verb to abort means to end a pregnancy before full development; the noun abortion names the event or procedure; and abortive can describe something incompletely developed or a treatment that halts a process early. Abortifacient specifically names the agent or instrument that causes the abortion.

Clinical and safety relevance. This is a sensitive area with important medical, legal, and ethical dimensions that differ widely between jurisdictions. The safe and lawful use of any such agent depends entirely on professional medical supervision and on the laws that apply in a given region. Attempting to end a pregnancy without qualified medical care can carry serious health risks. For this reason, questions in this area are properly directed to a qualified healthcare professional working within the applicable legal framework.

Distinction from related terms. A contraceptive prevents pregnancy from beginning and is therefore different in purpose and mechanism from an abortifacient, which acts after a pregnancy has been established. An emmenagogue is a substance that stimulates menstrual flow; some such agents have been historically associated with attempts to induce abortion, but the categories are not identical. “Abortifacient” denotes specifically that which provokes an abortion.

Etymology. From Latin abortus (a miscarriage, from aboriri, “to miscarry”) combined with faciens, “making” or “causing” (from facere, “to make, to do”) — literally, “causing abortion.”

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment, and it does not provide instructions for any procedure or advocate any course of action. Always consult a qualified healthcare professional, and be aware that laws and regulations on this subject vary by location.

Pronunciation: /əˈbɔːt/ · Part of speech: verb · Related noun: abortion · Field: obstetrics / general medicine

Definition. To abort is to eject an embryo or fetus, or to cause an embryo or fetus to be ejected, and so end a pregnancy before the fetus is fully developed. The word refers to the ending of a pregnancy before the point at which the fetus could survive independently.

Two senses of the term. In medical use, “abort” can describe events that are either spontaneous or induced:

• Spontaneous — the body naturally ejects the embryo or fetus without intervention. This is what is commonly called a miscarriage, and in medical terminology it may be referred to as a spontaneous abortion.
• Induced — the pregnancy is deliberately ended through medical or surgical means.

In both senses, the defining feature is that the pregnancy ends before the fetus is fully developed.

Broader medical use of “abort.” Beyond pregnancy, the verb abort is also used more generally in medicine to mean to stop a process before it is complete or to halt the development of a disease or condition. For example, a treatment may be said to abort a migraine attack or abort the progression of an infection — meaning it stops the process early, before it runs its full course. This usage shares the same core idea: ending something prematurely.

Related terminology. The noun abortion names the event or procedure of ending a pregnancy. An abortifacient is an agent that induces this. The adjective abortive can describe something that is incompletely developed, or a treatment intended to cut a process short (an abortive therapy). A threatened abortion and a missed abortion are clinical terms describing particular situations in early pregnancy.

Clinical relevance. The term appears throughout obstetric and gynaecological practice in both its specific (pregnancy-related) and general (process-halting) senses. Because the topic of pregnancy termination involves significant medical, legal, ethical, and personal dimensions that vary by region and circumstance, decisions in this area are made on an individual basis with appropriate professional and, where relevant, legal guidance.

Distinction from related terms. Miscarriage is the everyday term for spontaneous loss of a pregnancy. Stillbirth refers to the death of a fetus at a later stage, after the threshold of viability, which is distinct from abortion. Premature birth means delivery of a live infant before full term. “Abort” specifically denotes ending the pregnancy before the fetus is fully developed.

Etymology. From Latin aboriri, “to miscarry” or “to pass away” (ab- = away, amiss + oriri = to be born, to arise) — literally, to fail to come to birth.

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. It does not advocate any particular course of action. Always consult a qualified healthcare professional regarding any clinical questions, and be aware that laws and regulations on this subject vary by location.

Pronunciation: /æbˈɔːrəl/ · Part of speech: adjective · Opposite: oral (or adoral) · Field: anatomy / zoology

Definition. Aboral means situated away from, or opposite to, the mouth. It is a directional term used to describe the position of a structure relative to the mouth — pointing to the end or region farthest from the oral opening.

How it is used. Aboral is a term of relative position, like proximal/distal or anterior/posterior. It does not name a fixed point but describes direction with reference to the mouth: a structure is “aboral” if it lies on the side or end away from the mouth. Its counterpart, oral (or adoral), refers to the side toward or near the mouth.

Context in anatomy and zoology. The term is especially useful in describing organisms or structures arranged around a central axis, where “head” and “tail” terms are less meaningful:

• In radially symmetrical animals such as starfish, sea urchins, and jellyfish, the oral surface carries the mouth, while the opposite aboral surface faces away from it. For a starfish lying on the seabed, the oral surface is underneath and the aboral surface is on top.
• In the gastrointestinal tract, “aboral” can describe the direction away from the mouth and toward the far end of the gut — i.e., the direction in which food normally moves during digestion. Movement of intestinal contents proceeds in the aboral direction.

Clinical and scientific relevance. Using “aboral” allows precise description of direction along a tube or around a body axis without depending on the animal’s posture or orientation. In physiology, describing peristalsis or the flow of contents as moving in the aboral direction makes the intended direction unambiguous.

Distinction from related terms. Oral means toward or near the mouth. Adoral likewise refers to the region next to or toward the mouth. Distal means away from a point of attachment or origin, and proximal means toward it — similar in spirit but defined relative to a limb or structure’s base rather than the mouth. Aboral specifically takes the mouth as its reference point.

Etymology. From Latin ab- meaning “away from,” combined with oralis, from os / oris meaning “mouth” — literally, “away from the mouth.”

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional regarding any clinical questions or patient care decisions.

Pronunciation: /ˌæbɒˈkluːʒ(ə)n/ · Part of speech: noun · Field: dentistry / orthodontics

Definition. Abocclusion is a condition in which the teeth of the upper and lower jaws do not touch each other when the mouth is closed — that is, the opposing teeth fail to make contact. It is a type of malocclusion, the general term for any abnormal relationship or alignment between the upper and lower teeth.

How it works. Normally, when the jaws close, the upper and lower teeth meet in a regular, interlocking pattern that allows efficient biting and chewing. In abocclusion, this contact is absent: the teeth that should oppose one another remain apart, so the bite does not close properly. The lack of contact may involve some or all of the opposing teeth.

Context within dentistry. Abocclusion sits within the broader category of occlusion and malocclusion:

• Occlusion is the normal contact between the upper and lower teeth when the jaws are brought together.
• Malocclusion is any deviation from this normal contact — including crowding, overbite, underbite, crossbite, and open bite.
• Abocclusion specifically describes a situation where opposing teeth do not meet at all.

Clinical relevance. When teeth do not make proper contact, biting and chewing can become inefficient, and the forces of mastication may be distributed unevenly. Depending on the cause and extent, this can affect eating, speech, and the long-term health of the teeth and jaw joints. Assessment of how the teeth meet is a routine part of dental and orthodontic examination, and conditions affecting contact between the jaws may be managed with orthodontic or other dental treatment, depending on the individual case.

Distinction from related terms. Open bite describes a gap between the upper and lower front (or back) teeth when the jaws are otherwise closed, so the relevant teeth do not meet. Malocclusion is the umbrella term for any abnormal bite relationship. Occlusion refers to the contact itself. Abocclusion emphasises the absence of contact between opposing teeth.

Etymology. From Latin ab- meaning “away from,” combined with occlusion, from occludere, “to close up” (ob- = against + claudere = to close) — literally, a closing in which the teeth are held away from contact.

⚠️ Disclaimer: This explanation is provided for general educational and informational purposes only. It is not a substitute for professional medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional regarding any clinical questions or patient care decisions.