acknowledge

Etymology

Recorded since 1553, a blend of Middle English knowlechen (“to discover, reveal, acknowledge”) and aknowen (“to recognize, acknowledge”); the latter from Old English oncnāwan, ācnāwan (“to know, recognize, acknowledge”), from on + cnāwan (“to know”). Notice the preservation of /k/ word-internally (regularly spelled with ck as in back) while being lost word-initially. The prefix might have been influenced by Anglo-Norman a- (“on-, to-”). See knowledge. For the formation compare Latin agnōscō and Russian призна́ть (priznátʹ), with cognate roots.

verb

1. (transitive) To admit the knowledge of; to recognize as a fact or truth; to declare one's belief in
   to acknowledge the being of a god
   [N]ow ſuch a liue vngodly, vvithout a care of doing the wil of the Lord (though they profeſſe him in their mouths, yea though they beleeue and acknowledge all the Articles of the Creed, yea haue knowledge of the Scripturs) yet if they liue vngodly, they deny God, and therefore ſhal be denied, […] 1604, Jeremy Corderoy, A Short Dialogve, wherein is Proved, that No Man can be Saved without Good VVorkes, 2nd edition, Oxford: Printed by Ioseph Barnes, and are to be sold in Paules Church-yard at the signe of the Crowne, by Simon Waterson, →OCLC, page 40
   Addison: Pathfinder, you're making a mistake. Ryder: Maybe. But at least I'm willing to acknowledge it. 2017, BioWare, Mass Effect: Andromeda, Redwood City: Electronic Arts, →OCLC, PC, scene: Nexus
2. (transitive) To own or recognize in a particular quality, character or relationship; to admit the claims or authority of; to give recognition to.
3. (transitive) To be grateful of (e.g. a benefit or a favour)
   to acknowledge a favor
4. (transitive) To report (the receipt of a message to its sender).
   This is to acknowledge your kind invitation to participate in the upcoming debate.
5. (transitive) To own as genuine or valid; to assent to (a legal instrument) to give it validity; to avow or admit in legal form.
   One who has been sheriff may acknowledge a deed executed by him while in office. 1843, Thomas Isaac Wharton, A Digest of the Reported Cases Adjudged in the Several Courts Held in Pennsylvania, Together with Some Manuscript Cases