Action or inaction which binds a person legally even though it was not intended as such.
Action which is not intended as a direct acceptance of a contract will nevertheless stand as such as it implies recognition of the terms of the contract.
For example, if I display a basket of fruit in a marketplace and you come by, inspect an apple and then bite into it, you have acquiesced to the contract of sale of that apple.
Acquiescence also refers to allowing too much time to pass since you had knowledge of an event which may have allowed you to have legal recourse against another, implying that you waive your rights to that legal recourse.