: an antiaircraft gun
also : antiaircraft fire

Word History


British signalmen's telephone pronunciation of AA, abbreviation of antiaircraft entry 1

First Known Use

1917, in the meaning defined above

Time Traveler
The first known use of ack-ack was in 1917

Dictionary Entries Near ack-ack

Cite this Entry

“Ack-ack.” Dictionary, Merriam-Webster, Accessed 28 Mar. 2023.

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