2.9: Abbreviations and Acronyms

Abbreviations (the shortened form of a word or phrase) and acronyms (words formed from the initial letters of a phrase) are commonly used in technical writing. In some fields, including chemistry, medicine, computer science, and geographic information systems, acronyms are used so frequently that the reader can feel lost in an alphabet soup. However, the proper use of these devices enhances the reading process, fostering fluid readability and efficient comprehension.

Some style manuals devote entire chapters to the subject of abbreviations and acronyms, and your college library no doubt contains volumes that you can consult when needed. Here, I provide just a few principles you can apply in using abbreviations and acronyms, and in the next section I offer a table of some of the forms most commonly used by student writers.

Abbreviations

• Typically, abbreviate social titles (Ms., Mr.) and professional titles (Dr., Rev.).
• In resumes and cover letters, avoid abbreviations representing titles of degrees (e.g., write out rather than abbreviate "Bachelor of Science").
• Follow most abbreviations with a period, except those representing units of measure ("Mar." for March; "mm" for millimeter). See the table that follows for further guidance.
• Typically, do not abbreviate geographic names and countries in text (i.e., write "Saint Cloud" rather than "St. Cloud"; write "United States" rather than "U.S."). However, these names are usually abbreviated when presented in "tight text" where space can be at a premium, as in tables and figures.
• Use the ampersand symbol (&) in company names if the companies themselves do so in their literature, but avoid using the symbol as a narrative substitute for the word "and" in your text.
• In text, spell out addresses (Third Avenue; the Chrysler Building) but abbreviate city addresses that are part of street names (Central Street SW).
• Try to avoid opening a sentence with an abbreviation; instead, write the word out.
• When presenting a references page, follow the conventions of abbreviation employed by a journal in your field. To preserve space, many journals commonly use abbreviations, without periods, in their references pages (e.g., "J" for Journal; "Am" for "American").

Acronyms

• Always write out the first in-text reference to an acronym, followed by the acronym itself written in capital letters and enclosed by parentheses. Subsequent references to the acronym can be made just by the capital letters alone. For example:

Geographic Information Systems (GIS) is a rapidly expanding field. GIS technology . . .

• Unless they appear at the end of a sentence, do not follow acronyms with a period.
• Generally, acronyms can be pluralized with the addition of a lowercase "s" ("three URLs"); acronyms can be made possessive with an apostrophe followed by a lowercase "s" ("the DOD’s mandate").
• As subjects, acronyms should be treated as singulars, even when they stand for plurals; therefore, they require a singular verb ("NIOSH is committed to . . .").
• Be sure to learn and correctly use acronyms associated with professional organizations or certifications within your field (e.g., ASME for American Society of Mechanical Engineers; PE for Professional Engineer).
• With few exceptions, present acronyms in full capital letters (FORTRAN; NIOSH). Some acronyms, such as "scuba" and "radar," are so commonly used that they are not capitalized. Consult the table that follows in the next section to help determine which commonly used acronyms do not appear in all capital letters.
• When an acronym must be preceded by "a" or "an" in a sentence, discern which word to use based on sound rather than the acronym’s meaning. If a soft vowel sound opens the acronym, use "an," even if the acronym stands for words that open with a hard sound (i.e., "a special boat unit," but "an SBU"). If the acronym opens with a hard sound, use "a" ("a KC-135 tanker").

Click here to download a pdf of a table of commonly used abbreviations and acronyms.

Click here to open a table of commonly used abbreviations and acronyms

Table of Commonly used Abbreviations and Acronyms

Use this table to check the proper spelling, capitalization, and punctuation of commonly used abbreviations and acronyms. For a much more detailed listing of abbreviations and acronyms, you can check in the back pages of many dictionaries, or consult the Chicago Manual of Style(also available online to subscribers) or the free online version of the United States Government Printing Office Style Manual.

A or amp	ampere
a.m.	ante meridiem, before noon
Assembler	Assembler computer language
atm	standard atmosphere
Ave.	avenue
B.A.	Bachelor of Arts
BASIC	BASIC computer language
Blvd.	boulevard
BP	boiling point
B.S.	Bachelor of Science
Btu	British thermal unit
^oC	degrees Celsius
cd	candela
CDC	Centers for Disease Control
CFR	Code of Federal Regulations
CIA	Central Intelligence Agency
cm	centimeter
COBOL	COBOL computer language
Corp.	corporation
D	darcy
DEP	Department of Environmental Protection
DOD	Department of Defense
DOT	Department of Transportation
engg.	engineering
engr.	engineer
e.g.	exempli gratia, for example
EPA	Environmental Protection Agency
et al.	et alii, and others
etc.	et cetera, and so forth
^oF	degrees Fahrenheit
FBI	Federal Bureau of Investigation
FCC	Federal Communications Commission
FDA	Food and Drug Administration
fig.	figure
FORTRAN	FORTRAN computer language
ft	foot
gal.	gallon
ha	hectare
h	hour
HP	horsepower
HTML	hypertext markup language
Hz	hertz
i.e.	id est, that is
in	inch
Inc.	incorporated
K	Kelvin
kg	kilogram
kw	kilowatt
kWh	kilowatt-hour
l or L	liter
LAFTA	Latin American Free Trade Association
lb	pound
m	meter
mHz	megahertz
min.	minute
mol	mole
M.S.	Master of Science
NASA	National Aeronautics and Space Administration
neg	negative
NIH	National Institutes of Health
NIOSH	National Institute for Occupational Safety and Health
NM	nautical mile
NOAA	National Oceanic and Atmospheric Administration
NSF	National Science Foundation
OPEC	Organization of Petroleum Exporting Countries
OSHA	Occupational Safety and Health Administration
p.	page
Pascal	Pascal computer language
Ph.D.	Philosophiae Doctor, Doctor of Philosophy
p.m.	post meridiem, after noon
pos	positive
pp.	pages
pt.	pint
qt.	quart
radar	radio detecting and ranging
RPM	revolutions per minute
scuba	self-contained underwater breathing apparatus
sec. or s	second
sq	square
STP	standard temperature and pressure
temp	temperature
Univ.	university
URL	uniform resource locator
USGS	United States Geological Survey
vol.	volume

Self-Study

For comprehensive online acronyms dictionaries, especially for technical fields such as chemistry and medicine, I recommend these sites:

Online acronyms dictionary

Searchable acronyms database, sorted by discipline