noun \ˈak-ˌak\

Definition of ack–ack

  1. :  an antiaircraft gun; also :  antiaircraft fire

Origin and Etymology of ack–ack

British signalmen's former telephone pronoun of AA, abbreviation of antiaircraft

First Known Use: 1917

Learn More about ack–ack

Seen and Heard

What made you want to look up ack–ack? Please tell us where you read or heard it (including the quote, if possible).