|Publisher||Macquarie Dictionary Publishers|
|1981, 1991, 1997, 2005, 2009, 2013|
The Macquarie Dictionary is a dictionary of Australian English. It is generally held by universities and the legal profession to be the authoritative source on Australian English. It also pays considerable attention to New Zealand English. Originally it was a publishing project of Jacaranda Press, a Brisbane educational publisher, for which an editorial committee was formed, largely from the Linguistics department of Macquarie University in Sydney, Australia. It is published by Macquarie Dictionary Publishers an imprint of Pan Macmillan Australia Pty Ltd. In October 2007 it moved its editorial office away from Macquarie University to the University of Sydney.
The original version of the Macquarie Dictionary was based on Hamlyn's Encyclopedic World Dictionary of 1971, which in turn was based on Random House's American College Dictionary of 1947, which was based on the 1927 New Century Dictionary, which was based on The Imperial Dictionary of the English Language, which itself was based on Noah Webster's American Dictionary of the English Language second edition of 1841.
Since its first publication in 1981, its usage has grown so that over time, it has come to rival longer-established dictionaries from elsewhere in the English-speaking world as a standard authority on the English language within Australia.
The second edition was published in 1991 and it introduced encyclopedic content to many entries. The third edition, published in 1997, made use of an inhouse corpus of Australian writing, Ozcorp, to add a large number of examples of Australian usage, to give some of the flavour of an historical dictionary. This edition also gave a good coverage of English in Asia. The fourth edition, published in 2005, increases the number of citations, includes etymologies for many phrases and pays particular attention to Australian regionalisms. The fifth edition was published on October 2009 and places particular emphasis on words relating to the environment and climate change. The sixth edition was published on October 2013 and includes the usual update of new words along with a small collection of words from World War I. It leaves encyclopedic content to the dictionary online.
The dictionary records standard Australian English spelling, which is closer to British spelling than American spelling, with spellings like colour, centre, defence and practice/practise (noun/verb). It gives -ise spellings first, listing -ize spellings as acceptable variants, unlike the Oxford English Dictionary and some other dictionaries of British English, which continue to prefer -ize to -ise in spite of the opposite tendency amongst the British general public (see Oxford spelling).
One difference from British usage is the word program which the Macquarie Dictionary gives as the preferred spelling. 
A number of smaller versions are available, including a pocket edition, as well as companion volumes such as a thesaurus. The latest edition of the main complete version of the Macquarie Dictionary is the 6th, published in 2013. The Macquarie Australian Slang Dictionary published in 2004 is an up-to-date record of Australian slang. A range of dictionaries from the complete to a small dictionary is available as an IOS or Android application.
Macquarie Dictionary Online
The Macquarie Dictionary Online was initially the digital version of the print fourth edition. From 2013 it is the most complete version of the dictionary with greatest coverage of encyclopedic and non-encyclopedic entries. It offers spoken pronunciations. It is available by subscription.