What is ack short for in messages?


Ack is an abbreviation people use when messaging (via texts and online) to confirm understanding. For example, if your friend sends you information about an upcoming get-together, you might reply with "Ack. Will be there."

Not many people use ack, and the ones who do are usually slang-savvy teenagers or young adults. Also, Cathy, the comic strip character, is well known for using the abbreviation.

Since most people won't understand ack, you might want to use a different term to communicate understanding. Other options include OK, bet, SG, and gotcha.


We'll meet up at Andre's house tomorrow at 4
Ack. T4LMK

The ack salute

Related Slang


Updated April 4, 2023

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This page explains what the abbreviation "ack" means. The definition, example, and related terms listed above have been written and compiled by the team.

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