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APA Abbreviations


APA (American Psychological Association) style is most commonly used to cite sources within the social sciences. This resource, revised according to the 6th edition, second printing of the APA manual, offers examples for the general format of APA research papers, in-text citations, endnotes/footnotes, and the reference page. For more information, please consult the Publication Manual of the American Psychological Association, (6th ed., 2nd printing).

In APA, abbreviations should be limited to instances when a) the abbreviation is standard and will not interfere with the reader’s understanding and b) if space and repetition can be greatly avoided through abbreviation.

There are a few common trends in abbreviating that you should follow when using APA, though there are always exceptions to these rules. When abbreviating a term, use the full term the first time you use it, followed immediately by the abbreviation in parentheses.

According to the American Psychological Association (APA), abbreviations are best used only when they allow for clear communication with the audience.

Exceptions: Standard abbreviations like units of measurement do not need to be written out. APA also allows abbreviations that appear as words in Merriam-Webster’s Collegiate Dictionary to be used without explanation (IQ, REM, AIDS, HIV).

State names do not need to be written out in reference entries or the Methods section of a research paper. In these locations, standard two-letter abbreviations are permitted. However, no guidelines in the Manual exist for referring to states in the body of a document. The OWL recommends using consistent, sensible formatting for ordinary usage of state names.

Do not use periods or spaces in abbreviations of all capital letters, unless it is a proper name or refers to participants using identity-concealing labels:

P. D. James, J. R. R. Tolkien, E. B. White or F.I.M., S.W.F.

Exceptions: Use a period when abbreviating the United States as an adjective (U.S. Marines or U.S. Senator)

Use a period if the abbreviation is Latin abbreviation or a reference abbreviation:

etc., e.g., a.m. or Vol. 7, p. 12, 4th ed.

Do not use periods when abbreviating measurements:

cd, ft, lb, mi, min

Exceptions: Use a period when abbreviating inch (in.) to avoid confusion.

Units of measurement and statistical abbreviations should only be abbreviated when accompanied by numerical values:

7 mg, 12 mi, M = 7.5
measured in milligrams, several miles after the exit, the means were determined

Only certain units of time should be abbreviated.

Do not abbreviate:

day, week, month, year

Do abbreviate:

hr, min, ms, ns, s

To form the plural of abbreviations, add s alone without apostrophe or italicization.

vols., IQs, Eds.

Exception: Do not add s to pluralize units of measurement (12 m not 12 ms).

Abbreviations in Citations

Citations should be as condensed as possible, so you should know the basic rules of abbreviation endorsed by the APA to provide your readers with reference information.

Always abbreviate the first and middle names of authors, editors, etc.

Shakespeare, W., Chomsky, N.

Use the following abbreviations within citations (take note of capitalization):

APA Citation Abbreviations
Book Part Abbreviation
edition ed.
revised edition Rev. ed.
Second Edition 2nd ed.
Editor(s) Ed. or Eds.
Translator(s) Trans.
No date n.d.
Page(s) p. or pp.
Volume(s) Vol. or Vols.
Number No.
Part Pt.
Technical Report Tech. Rep.
Supplement Suppl.