Also found in: Dictionary, Encyclopedia.
A treaty between Australia, New Zealand, and the United States stating that signatories will coordinate and cooperate with one another on defense issues, especially those affecting the South Pacific. It came into effect in 1951. In the mid-1980s, the United States and New Zealand had a dispute over nuclear ships and now do not consider themselves bound by ANZUS with respect to each other. However, they both maintain treaty obligations with respect to Australia.