1 of 2


used to express mild alarm or dismay
You should see the big wad of lint I just plucked from the trap of my clothes dryer. Ack! Where does all of that come from?Mary Hunt


2 of 2


acknowledge; acknowledgment

Word History

First Known Use


2001, in the meaning defined above

Time Traveler
The first known use of ack was in 2001

Dictionary Entries Near ack

Cite this Entry

“Ack.” Dictionary, Merriam-Webster, Accessed 20 May. 2024.

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