10.8. Abbreviations and symbols

The prime consideration when using abbreviations should be to help the reader.

The prime consideration when using abbreviations should be to help the reader. First, they should be easily understood. So when an abbreviation that may not be familiar to readers first occurs, it is best to write out the full term followed by the abbreviation in brackets:

If your document contains a lot of abbreviations, consider including a list of them and their meanings at the beginning or end of the document.

Second, they should not be used needlessly. If an abbreviation occurs only once or twice, it is best to dispense with it altogether and use the full form. In repeated references, it is also often possible to use a short form instead of an abbreviation:

Acronyms are words formed from the first (or first few) letters of a series of words, and are pronounced as words (Benelux, NATO, etc.). They never take full stops. Some of these are formed from French titles (e.g. Cedefop).

Initialisms are formed from the initial letters of a series of words and each separate letter is pronounced (BBC, MEP, USA, etc.).

As a general principle, acronyms and initialisms do not have a full stop between the capitals.

Except for well-known acronyms and initialisms, write out the full term followed by the abbreviation in brackets on its first mention in a document (or, where necessary, in long reports, on its first mention in each section):

Generally speaking, acronyms do not take a definite article (NATO, REACH, etc.), but initialisms do (the UK, the BBC, the EU, etc.). However, established usage may be different, particularly for the names of companies (ICI, IBM, etc.) and universities (UEA, UCL, etc.).

Acronyms with up to five letters are uppercased:

Exceptions: Tacis and Phare, which are no longer considered acronyms

Acronyms with six letters or more should normally be written with an initial capital followed by lower case. Thus:

Exceptions: organisations that themselves use upper case (such as UNESCO and UNCTAD) and other acronyms conventionally written in upper case.

Note the difference between a truncation, in which the end of the word is deleted (e.g. vol., co. or inc.), and a contraction, in which the interior of the word is removed (e.g. Mr, Dr, contd or Ltd). Truncations take a full stop, but contractions do not.

‘No’ as in ‘No 1’ is a contraction of ‘numero’. It is never followed by a full stop, and its plural is Nos (no point).

Do not abbreviate Article to ‘Art.’ in running text. Avoid using the § sign, which means ‘section’ in English but ‘paragraph’ in other languages, unless the section referred to is itself marked by such a symbol. For example, ‘l’article 3 §1’ should read ‘Article 3(1)’ in English.

Plurals of acronyms, initialisms and figures do not take an apostrophe unless they are in the possessive:

but

While an abbreviation ending in ‘S’ should also take an ‘s’ for the plural form, e.g. SOSs, this may look clumsy if used frequently within the same text. In such cases, one possibility is to allow the abbreviation to stand for both the singular and the plural form, e.g. PES (public employment service(s)) or RES (renewable energy source(s)), though care should always be taken to avoid ambiguity and the full plural term may be preferable.

Units of measurement and scientific symbols such as ‘ha’, ‘km’, ‘mg’, etc. do not need a final full stop. They are not closed up to figures and do not have plurals:

See Annexes A3 and A4.