The Australian National Dictionary includes only Australian words and meanings – those that occur exclusively in Australia, that are used more intensively in Australia than elsewhere, or that have a special significance in Australia. The one-volume first edition (1988) included 10,000 such words and meanings, illustrated by 60,000 quotations. The second edition, the product of research at the Australian National Dictionary Centre at the Australian National University, is a two-volume work, now with 16,000 Australian words and meanings illustrated by 123,000 quotations.

The large increase in quotations derives in part from the evidence provided for the new entries, but also from the updating of the entries that were in the first edition. The quotation evidence for both new and old entries has been greatly enriched by use of the searchable Australian newspaper section of  Trove at the National Library of Australia.

How do we account for the large increase in words and meanings since 1988? It would be exciting, if implausible, to believe that Australian English has increased its lexicon by more than fifty per cent since 1988.

Many of the new entries derive from the pre-1988 period. The editors of the first edition often did not have the evidence to evaluate whether a word was Australian or not, but the world of the internet and numerous electronic databases have made this an easier task, and much more material from the pre-1988 period has been added: food terms such as Boston bun, chocolate crackle, copha, Devonshire tea, fairy bread, long soup, pluto pup, slice; words for people, such as bush baptist, callithumpian, Mrs Kafoops; terms that many would not suspect to be Australian such as blood and bone, bunny rug, kitchen tidy, light globe; and numerous others.

As a matter of editorial policy, I have also greatly expanded the colloquial element in the dictionary. As a result, many more slang-like terms from the earlier period are now included, the range indicated by the following selection of idioms: I don't know if I'm Arthur or Martha; your blood's worth bottling; a cup of tea, a Bex, and a good lie down; dry as a dead dingo's donger; full up to dolly's wax; stacks on the mill; he wouldn't know if a tram was up him unless the conductor rang the bell.

These are all older terms, but the lexicon has continued to expand since the 1980s. The triumphant word of the period is undoubtedly bogan and its derivatives boganhood, boganic, boganism, boganity, boganland, boganness. New words have come from all the significant semantic areas, including, for example: alcohol and other drugs (chroming, Goon of Fortune, yandi), the body (ted, tockley), clothing (double pluggers, budgie smugglers), food (kransky, skippy syndrome, yiros), terms for people (clog wog, grey nomad, ranga, toolie), sport (falcon, pocamelo, shirtfront, walla rugby), transport (hoon law, wogmobile), entertainment and leisure (chook lit, doof, goanna pulling). A series of words and phrases new to this edition derive from literature, radio, and film: the bastard from the bush; Bib and Bub; Blue Hills; Crocodile Dundee; Dad and Dave; Don's Party; Ginger Meggs; Hanrahan; magic pudding; straight to the pool room; sunburnt country; sunlit plains; there's movement at the station; thumbnail dipped in tar; we'll all be rooned.

Words from Aboriginal languages and culture are a significant source of expansion. Whereas the first edition included about 250 words from sixty languages, the new edition includes more than 450 words from 100 Aboriginal languages, with the Western Australian Noongar language now overtaking the Sydney language as the greatest contributor. Most of the borrowings from Aboriginal languages occurred during the early contact period, but this new edition contains evidence of a continuing transfer of words from Aboriginal languages into Australian English. There are also numerous examples of English terms used to render Aboriginal concepts and traditional culture (keeping place, saltwater people, secret women's business, songline).

Richard Trench, in the 1857 lecture that was instrumental in getting the Oxford English Dictionary project started, stressed that a historical dictionary 'is an historical monument, the history of a nation contemplated from one point of view'. Words encode the values of a society, and it is the aim of the Australian National Dictionary to document and analyse the history of the words and meanings that have shaped Australia.

Bruce Moore, editor of the second edition of the Australian National Dictionary (Oxford University Press, 2016), was director of the Australian National Dictionary Centre from 1994 to 2011.