Abbreviations and contractions

Abbreviations and contractions are alike in that they both shorten individual words. They differ in how much they retain of the full word.

Abbreviations consist of the first letter and sometimes other letters from the word, but not the last letter. For example, approximately becomes approx in its abbreviated form.

Contractions consist of the first and last letters of a word (and sometimes other letters in between). For example, highway becomes hwy as a contraction.

Common abbreviations

Some common abbreviations are described below:

• e.g. is short for Latin exempli gratia (meaning for example). It indicates that the list that follows is incomplete. It is especially useful where space is limited. It should only be used in tables and figures, and in parentheses in running text. In formal writing, it should be spelled out in full

• i.e. is short for Latin id est. It means in other words or that is. Like e.g., it should only be used in parentheses or in tables and figures

• etc is short for et cetera. It is used at the end of a list to show that the list could be extended. It can be used instead of putting e.g. at the start of the list (but not in addition to e.g.)

• et al is short for et aliae or et alii (meaning and other people). It is used in formal writing to avoid a long list of names of people who have written something together
  Jones et al (2007) reported …

  The results showed … (Jones et al 2007)

  See Author-date in-text citations for further advice on using et al in citations.

If you are writing web content, be aware that some screen readers do not recognise some abbreviations and will just read them as if they are a word, which can be confusing for listeners. For this reason, it is a good idea to spell out abbreviations in web content:

Days of the weeks and months are abbreviated to 3 letters (see Date and time systems).

Punctuation of abbreviations

Most abbreviations should be set without full stops (except for e.g. and i.e. mentioned above):

However, some organisations still commonly use stops. Be guided by your organisation’s style guide if this is the case.

Latin abbreviations that have 2 letters may cause confusion among readers and be recited incorrectly by screen readers. For these, use 2 stops (not a single stop):

Also, do not follow these abbreviations with a comma:

Abbreviations that require full stops

In line with accepted species nomenclature, use full stops for the abbreviations for species, both singular and plural:

Use a full stop when abbreviating number to no. Without the full stop, the abbreviation may be misread, although the following number clarifies its role. No. can be used when the word number itself would be too bulky or cumbersome, or can be omitted. Other more specific words can also be used to indicate numbers within a series:

A hash sign (octothorp) (e.g. #65) is also widely used to flag a following number, in citations, addresses and elsewhere.

Abbreviations that never take full stops

Do not include a full stop after unit abbreviations:

See Numbers used with units for more details on units.

Punctuation of contractions

Contractions do not take full stops:

Plurals of abbreviations and contractions

Add an s, without an apostrophe, for abbreviations or contractions that take a plural:

Note that unit abbreviations never take a plural s (see also Numbers used with units):

Syllabic abbreviations

A form of abbreviation that is becoming more common is the syllabic abbreviation. Syllabic abbreviations are formed from syllables of words in the full term (usually the first syllables):

Capitalisation and hyphenation of this type of abbreviation varies case by case. Check the official titles for names of organisations (e.g. FedEx), the accepted style in a particular academic field (e.g. statistics for ANOVA) or a dictionary for common usage.

Abbreviation of academic and professional qualifications

Academic and professional qualifications are often shortened to appear after a name or in a list.

Use the shortened form of the qualification. Do not use full stops:

For an honours degree, include Hons in brackets with no space between the abbreviation and the bracket:

If the qualification has a subject area, include it in brackets in full, with no space between the abbreviation and the bracket:

If including a list of qualifications after a name, list the academic qualifications first, in order of achievement, then any professional qualifications or accreditations; do not use a comma after the name or between the qualifications:

For a person with a PhD, either use the qualification PhD after the name or the title Dr before, but not both:

Abbreviation of honours and awards, and membership of parliament

‘Postnominals’ refers to the letters that follow a person’s name to indicate any honours or awards they have received.

If including a list of honours and awards after a name, list the honours and awards with the most important first; do not use a comma after the name or between the postnominals:

If academic qualifications are also listed after the person’s name, put these before the honours and awards:

Abbreviations for membership of parliament are shown after other postnominals: