key: cord-0035793-mqa93hwj
authors: Ribes, Ramón; Iannarelli, Palma; Duarte, Rafael F.
title: Acronyms and Abbreviations
date: 2009-04-07
journal: English for Biomedical Scientists
DOI: 10.1007/978-3-540-77127-2_16
sha: 295d2ba672bb8815f78f7ab3994d6259cf5adf12
doc_id: 35793
cord_uid: mqa93hwj

n many fields today abbreviations and acronyms are common. They provide a useful tool for shortening long words or expression in order to save time and space. Some well-known general examples are DVD (digital versatile disc), UNICEF (United Nations International Children’s Emergency Fund), NASA (National Aeronautics and Space Administration), and UN (United Nations). Abbreviations are extensively used in the scientific and medical communities. It is common practice to use abbreviations for long names of many clinical diseases and procedures, and for scientific techniques that have to be repeated many times in medical or scientific papers, posters, and oral presentations. This can cause substantial communication difficulties for individuals who are not familiar with English abbreviations in their field. The example below is meaningless to individuals who are not familiar with the abbreviations used.

Many individuals, including native English speakers, do not know the difference between an acronym and an abbreviation. Acronyms and abbreviations are formed by combining the first letter or letters of several words. All acronyms are abbreviations, but not all abbreviations are acronyms. An acronym is a special type of abbreviation that can be pronounced as a single word (it can be said), while all other abbreviations are pronounced letter by letter (you say each letter individually or spell it out).

AIDS is an acronym for Acquired Immune Deficiency Syndrome because you say the abbreviation as a word ("aydz"); whereas HIV is an abbreviation for Human Immunodeficiency Virus (in this case you say each letter individually).

It can be extremely frustrating and time-consuming trying to find out what certain commonly used acronyms and abbreviations mean. Abbreviations that some consider universally known may be obscure to others. In addition, shortened forms used in one country may not be understood in another. In order to eliminate guesswork and prevent frustration, we have put together an alphabetized list of the most commonly used English acronyms and abbreviations in biomedical research. We feel that having a central reference list at your fingertips could be quite helpful for your scientific communications.

Apply the following guidelines when using abbreviations:

• On the first occurrence of an abbreviation, spell out the full term, with the abbreviation in brackets. Thereafter the abbreviated form may be used by itself.

For example, Oligodendrocytes (OLs) are the cells responsible for producing a fatty protein called myelin. Each OL can supply myelin for several axons and each axon can be supplied by several OLs. 

p for page and pp for pages (not ps or pgs) l for line and ll for lines (not ls) c for column and cc for columns (not cs) Exception 2: Singular and plural units of measure are abbreviated the same. An s is generally not added to the plurals.

If the abbreviation contains a period (full stop), form the plural with an apostrophe and an s ('s). This is probably because it looks more awkward without apostrophes: 

The United Nations International Children's Emergency Fund is a voluntarily funded agency. UNICEF was created on December 11, 1946.

The choice of an indefinite article (a or an) before letter-by-letter abbreviations depends on the pronunciation of the first letter of the abbreviation, not on the written representation of the first letter. If the abbreviation begins with a consonant sound, use a. If it begins with a vowel sound, use an.

an mRNA molecule -although "m" is a consonant, we use the an article because the first sound we make is an "em" sound. an X-ray -this abbreviation begins with a consonant letter, but sounds like it starts with a vowel. The first sound we make is an "eks" sound.

There are several abbreviation styles used today. The only rule one should remember is to have a consistent style.

However, some acronyms are no longer capitalized. Examples are laser, radar and sonar.

• A period is sometimes written after an abbreviated word (there is no strict rule). The general modern trend is to omit periods from abbreviations (to avoid an appearance of clutter).

Organizations, countries, and units of measure are not generally followed by periods. • If a sentence ends with an abbreviation that requires a period, do not add another period.

The technician will be here at 4 p.m. not The technician will be here at 4 p.m.

• Abbreviations of chemicals from the periodic table always start with a capital letter; if there is a second letter, it is always lowercase.

For example, N Nitrogen O Oxygen Na Sodium Zn Zinc • Do not divide abbreviations, or a numerical value followed by a unit of measure, between lines on a page.

………………10 mg not……………AI not………………10

A A Adenine or alanine aa Amino acid or aminoacyl Ab Antibody ABU L-a-Aminobutyric acid ABZ 2-Aminobenzoyl AC Accession number ac Acetyl Ac Actinium Ac-CO A Acetyl-coenzyme A AChE Acetylcholinesterase 

Always abbreviate units when reporting numerical information. However, if you write the number out in full, you must spell out the unit of measurement. Always put a space between the number and the unit. When starting a sentence with a number and unit, both must be spelled out as words. Abbreviations for most units of measurement use small letters. 

African green monkey kidney cell line EC Embryonal carcinoma (human) EJ Human bladder cancer cell line GH3 Rat pituitary tumor cell line HaCaT Human keratinocyte cell line HEK Human embryonic kidney HeLa Henrietta Lacks (human cervical cell line) HL-60 Human leukemia cell line MCF-7 Human breast cancer cell line MDCK Madin-Darby canine kidney NS0 Mouse myeloma cell line PC12 Chromaffin cell line (rat) SCLC Small cell lung cancer cell line SPEV Swine kidney cell line SW480 Human colon cancer cell line U87 Human glioblastoma-astrocytoma cell line U343 Human astrocytoma cell line