ack-ack

Noun

WORDNET DICTIONARY

ack-ack(n = noun.artifact) ack-ack gun, antiaircraft, antiaircraft gun, flack, flak, pom-pom - artillery designed to shoot upward at airplanes; Array

has particulars: bofors gun

is a kind of gun

has parts: predictor

ack-ack, n. [from AA, meaning antiaircraft pronounced ack-ack by British signalmen.].

Artillery designed to shoot upward at airplanes; antiaircraft artillery. [WordNet 1.5]

ack-ack, adj. & n. colloq.
--adj. anti-aircraft.
--n. an anti-aircraft gun etc.

Etymology

formerly signallers' name for the letters AA

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