an act of accepting that something exists or is true, or that something is there

an act or a statement expressing thanks to somebody; something that is given to somebody as thanks

The flowers were a small acknowledgement of your kindness.

I was sent a free copy in acknowledgement of my contribution.

She is still waiting for some acknowledgement from her fellow academics.

a letter or an email saying that something has been received

I didn't receive an acknowledgement of my application.

It may be appropriate to request a written acknowledgement of receipt.

I wrote to them but never got any acknowledgement.

a statement, especially at the beginning of a book, in which the writer expresses thanks to the people who have helped

LEARNit Dictionary