heavy ack

What Is An Ack Ack? : an antiaircraft gun also : antiaircraft fire. Where does the term Ack Ack come from? Word origin. C20: British army World War I phonetic alphabet for AA, abbreviation of anti-aircraft. ‘Saint Luke’s summer’ English. What is Ack Ack slang for? ack-ack in American English (ˈækˌæk ) noun. Slang. an