/ Thesaurus / A Synonyms of ack ack Find synonyms for: Noun1. antiaircraft, antiaircraft gun, flak, flack, pom-pom, ack-ack, ack-ack gun, gunusage: artillery designed to shoot upward at airplanesWordNet 3.0 Copyright © 2006 by Princeton University. All rights reserved. Related Content Daily Word Quiz: arboreal Analogy of the Day: Today’s Analogy Spelling Bee: Today’s Spelling Bee Frequently Misspelled Words Frequently Mispronounced Words Easily Confused Words Writing & Language