ack-ack

IPA/ˌæk ˈæk/
IPA/ˌæk ˈæk/

ack-ack — noun

1. the repeated shooting of shells or bullets from the ground at aircraft flying ov

1.nounC1
Definition

the repeated shooting of shells or bullets from the ground at aircraft flying overhead

Example

Nadia could hear the ack-ack from miles away as enemy planes approached the city.

uncountable noun describing anti-aircraft gunfire

During the air raid, the soldiers fired ack-ack into the night sky for hours.

Common collocations
  • heavy ack-ack
  • ack-ack barrage
  • ack-ack fire
Synonyms
  • antiaircraft fire

    the formal equivalent, preferred in official military reports

  • flak

    from German Flak, common in both British and American WWII accounts

  • AA fire

    military abbreviation, concise but technical

Usage Note

Usually uncountable. Refers to the action or sound of anti-aircraft fire, not an individual weapon.

Common Mistakes

We heard two ack-acks in the distance.
We heard ack-ack in the distance.
Ack-ack is uncountable when referring to the sound or firing.

2. a large gun or cannon that shoots at aircraft flying overhead, typically placed

2.nounC1
Definition

a large gun or cannon that shoots at aircraft flying overhead, typically placed on the ground or on a ship

Example

The old ack-ack sat rusting at the edge of the military museum yard.

countable noun referring to the weapon

Erik helped operate an ack-ack during the battle, passing heavy shells to the loader.

Common collocations
  • ack-ack battery
  • ack-ack crew
  • ack-ack position
  • ack-ack gun
Synonyms
  • antiaircraft gun

    the formal term, widely used in technical and historical writing

  • AA gun

    abbreviated form, common in military contexts

  • flak cannon

    informal term of German origin, used in WWII narratives

Usage Note

Countable noun referring to the weapon itself. Common in historical accounts of World War II and often used with an article (an ack-ack, the ack-ack).

Common Mistakes

The soldier fired ack-ack at the plane.' (when meaning the weapon)
The soldier fired an ack-ack at the plane.
Adding 'an' makes it clear you mean the gun, not the gunfire.

Synonym discussion

Sense: noun/2

Ack-ack, antiaircraft gun, AA gun, and flak cannon all refer to weapons designed to shoot at aircraft, but they differ in register and origin. 'Antiaircraft gun' is the formal, neutral term used in military manuals and technical writing. 'AA gun' is an abbreviation common in armed forces communication. 'Ack-ack' was British military slang from World War I and II, derived from the phonetic pronunciation of 'AA', and carries a more informal, historical tone. 'Flak cannon' comes from the German Flak (Fliegerabwehrkanone) and was adopted by Allied forces during WWII. For example: 'The museum displayed a restored World War II antiaircraft gun' sounds formal, while 'The soldiers called the old ack-ack by its nickname' feels conversational and period-specific.

ack-ack ↗antiaircraft gunAA gunflak cannon

Common collocations

Phrases

  • ack-ack fire
  • ack-ack barrage

Prepositions

  • under ack-ack
  • from ack-ack

Etymology

English

Ack-ack comes from the British Army's First World War phonetic alphabet, where the letter 'A' was spoken as 'ack'. Because 'AA' was the standard abbreviation for 'anti-aircraft', soldiers began calling anti-aircraft fire 'ack-ack'. The term became widely known during the London Blitz and other World War II campaigns, where it described both the gunfire and the weapons themselves.

First known use

1917

1917, in the meaning defined above