Abbreviations and contractions

Did you know? Modern usage is trending towards no full stops in abbreviations.

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.

This section covers:

Common abbreviations

Some common abbreviations are described below (see Punctuation of abbreviations for guidance about using full stops in these abbreviations):

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

Inflammation can be seen in many organs (eg brain, kidney, liver).

Inflammation can be seen in many organs – for example, brain, kidney and liver.

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

They are open only on weekdays (ie Monday to Friday).

They are open only on weekdays – that is, Monday to Friday.

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

He needed to buy fruit (eg apples, bananas, grapes).
He needed to buy fruit (apples, bananas, grapes, etc).
He needed to buy fruit (eg apples, bananas, grapes, etc).

  • et al, short for et aliae or et alii (meaning and other people) 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 Published references for further advice on using et al in text citations.

If you are writing web content, be aware that some screen readers do not recognise these and other 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:

for example   instead of   eg

that is   instead of   ie

and so on   instead of   etc

Days of the weeks and months are abbreviated to 3 letters (see Dates).

Return to top

Punctuation of abbreviations

Most abbreviations should be set without full stops:

approx     Ave     cf     eg     ie     Mon     vol     et al

However, some organisations still commonly use stops (especially in eg and ie). Be guided by your organisation’s style guide if this is the case.

Use either no stops or 2 stops in Latin abbreviations that have 2 letters, not a single stop:

eg   or   e.g.

Also, do not follow these abbreviations with a comma:

eg flowering plants
eg, flowering plants   or   e.g., flowering plants

Abbreviations that require full stops

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

sp. [singular]     spp. [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:

issue no. 15     issue 15

batch 65     report 23     lot 1115/A

A hash sign (octothorp) (eg #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:

10 g     5 mL     2.5 km

See Numbers used with units for more details on units.

Return to top

Punctuation of contractions

Contractions do not take full stops:

Dr     Mr     Qld     Pty Ltd     wt/wt
Return to top

Plurals of abbreviations and contractions

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

They had 6 PhDs between them   not   They had 6 PhD’s …

Note that unit abbreviations never take a plural s (see also Singular or plural units):

5 mL   not   5 mLs

10 km   not   10 kms

Return to top

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):

ANOVA [analysis of variance]

FedEx [originally Federal Express]

hi-fi [high fidelity]

INTERPOL [International Criminal Police Organization]

IPEd [Institute of Professional Editors]

Gestapo [from Geheime Staatspolizei]

modem [from modulator–demodulator]

satnav [satellite navigation]

webcam [web camera]

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

Return to top

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:

BA [Bachelor of Arts]

BEng [Bachelor of Engineering]    

DipE [Diploma of Education]   

MSc [Master of Science]    

PhD [Doctor of Philosophy]    

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:

BA(Communications) [Bachelor of Arts in Communications]

MSc(Microbiology) [Master of Science in Microbiology]

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:

Jane Smith BSc PhD MBA AE

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

Dr Peter Brown BSc(Hons)
Peter Brown BSc(Hons) PhD

Return to top

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:

Ms Andrea Smith AC MBE

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

Ms Andrea Smith BA(Hons) AC MBE

Abbreviations for membership of parliament are shown after other postnominals:

Ms Andrea Smith BA(Hons) AC MBE MP
Return to top

User login

... or purchase now

An individual subscription is only A$60 per year

Group and student discounts may apply

Australian manual of scientific style Start communicating effectively