In this post, we discuss abbreviations, acronyms and initialisms and give some tips on their use.

First, let’s define these three terms:

• Abbreviation: a shortened form of a word or a phrase, for example “km” for kilometre”, “Dr” for “doctor”.
• Initialism: an abbreviation made up of a set of capitalised letters, for example, BBC (British Broadcasting Corporation), WHO (World Health Organisation).
• Acronym: an initialism that is pronounced as a word, for example, AIDS (acquired immunodeficiency syndrome), NASA (National Aeronautics and Space Administration),

For the rest of this post, the term abbreviation is used but the guidance described applies equally to initialisms and acronyms.

Standard and non-standard abbreviations

In science, there are many standard abbreviations in use, such as units of measurement, (for example “m” for “metre”, “kg” for “kilogram”) and chemical symbols (for example H for hydrogen, Cl for chlorine). These abbreviations do not need to be spelled out at their first use.

There are also non-standard abbreviations, however, that are specific to particular fields of science. These should be written out in full at their first use (in both your abstract and your paper itself) and followed by the abbreviated form in brackets, for example, “computational fluid dynamics (CFD)”, “the World Health Organization (WHO)”.

Common errors to avoid when using abbreviations

Writers sometimes assume that because an abbreviation is written in capitals that this means capital should be used when the abbreviation is written out in full. This is only generally the case if the abbreviation includes proper nouns or the name of or more individuals.

For example, with the term “Akaike information criterion (AIC)”, only “Akaike” should be capitalised, as it is the name of the statistician who formulated the criterion. However, when writing “UK” out in full, both words should be capitalised: “United Kingdom”.

Another important point to consider when writing abbreviations is the use of the correct article before the abbreviation. The article you need to use will depend on how the abbreviation is pronounced.

If the abbreviation you are using is pronounced with a vowel sound, the indefinite article that should be used with it is “an”. For example, “an LFD test” (where “LFD” is the abbreviation of “lateral flow device”).

If the abbreviation you are using is pronounced with a consonant sound, the indefinite article that should be used with it is “a”. For example, “a PCR test” (where “PCR” is the abbreviation of “polymerase chain reaction”).

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