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OASIS

Abbreviations can help you avoid repeating lengthy, technical terms throughout a piece of writing, but they should be used sparingly to prevent your text from becoming difficult to read.

Basics

To use an abbreviation, write out the term or phrase on first use, followed by the abbreviation in parentheses.

Many abbreviations take the form of acronyms or initialisms, which are abbreviations consisting of the first letter of each word in a phrase. Note that the abbreviation uses all capital letters, and there are no periods between the letters.

If you use the phrase three times or fewer, it should be written out every time.

  • National Institute of Mental Health (NIMH)
  • Better Business Bureau (BBB)
  • Centers for Disease Control and Prevention (CDC)
  • American Psychological Association (APA)

Using Abbreviations in Your Writing

After introducing the abbreviation, use the abbreviation by itself, without parentheses, throughout the rest of the document.

The patient had been diagnosed with traumatic brain injury (TBI) in March of 2014. According to the Centers for Disease Control and Prevention (CDC, 2015), people with TBI often have difficulty with memory and concentration, physical symptoms such as headaches, emotional symptoms such as sadness and irritability, and difficulty falling asleep. Although the patient explained that she experienced frequent headaches and difficulty concentrating, she had not been regularly taking any medication for her TBI symptoms when she visited the clinic 6 months after her diagnosis.

Making an Abbreviation Plural

Add an “s” to an abbreviation to make it plural. Do not add an apostrophe.

I work with five other RNs during a typical shift.

Exceptions

Commonly Used Abbreviations

Commonly used acronyms and abbreviations may not need to be written out. If an abbreviation appears as a word in Merriam-Webster’s Collegiate Dictionary, then it does not need to be written it out on first use. Examples include words such as IQ, REM, RN, and HIV.

Defining Abbreviations Within Citations

When introducing an abbreviation within a narrative citation, use a comma between the abbreviation and the year.

The Department of Education (DOE, 2023)

If introducing an abbreviation within a parenthetical citation, put the abbreviation in brackets to avoid nesting parentheses.

(The Department of Education [DOE], 2023)

Don’t Use Abbreviations in References

Other than abbreviations prescribed by APA in reference list elements (such as “ed.” for “edition” and “n.d.” for “no date”), do not use abbreviations in the reference list. For example, a source authored by the Centers for Disease Control and Prevention would not be abbreviated as CDC in a reference.

Units of Measure

If using an abbreviation for a unit of measure with a numerical value, you do not need to write the term out on first use. For example, instead of writing “12 grams,” you can simply use “12 g.” If, however, you use a unit of measure without a numerical value, write the term out (such as “several grams”).

Time, Latin Terms, and Statistics

Abbreviations for time, common Latin terms, and statistical abbreviations also follow specific rules. See APA 7, Sections 6.28, 6.29, and 6.44 for more information.

United States

In APA style, "United States" should always be spelled out when it is used as a noun or location.

In the United States, 67% reported this experience.

United States can be abbreviated as "U.S." when it is used as an adjective.

U.S. population and U.S. Census Bureau.

Key Takeaways

Check Your Understanding

Related Resources

Abbreviations Video

 


 

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