British signalmen's telephone pronunciation of AA, abbreviation of antiaircraft entry 1
1917, in the meaning defined above
ack
ack-ack
ackee
“Ack-ack.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ack-ack. Accessed 30 Dec. 2024.
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