The Macquarie Dictionary is a dictionary of Australian English. It is considered by many to be the standard reference 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 now published by Macquarie Dictionary Publishers, an imprint of Pan Macmillan Australia Pty Ltd. In October 2007 it moved its editorial office from Macquarie University to the University of Sydney, and later to the Pan Macmillan offices in the Sydney central business district.

A dictionary is a listing of lexemes from the lexicon of one or more specific languages, often arranged alphabetically, which may include information on definitions, usage, etymologies, pronunciations, translation, etc. It is a lexicographical reference that shows inter-relationships among the data.