acknowledge

Behind the word lies a blend recorded since 1553: Middle English aknowen, 'to recognize', crossed with knowlechen, which is built on the noun knowledge. It takes a direct object, as in the King James Bible of 1611 (I acknowledge my transgressions), or a that-clause. In the passive it pairs naturally with to be, as in Macaulay's ends generally acknowledged to be good.

Here the object is usually a person whose standing is owned or refused, not a fact. In Shakespeare's Romeo and Juliet the refusal amounts to disowning someone: I'll ne'er acknowledge thee. A useful pattern is the reflexive with as, where someone acknowledges himself as an old friend. That means owning an identity, while the 'admit as true' meaning concedes a point.

Correspondence keeps a set formula for this sense: This is to acknowledge your kind invitation. The object is the message itself, and the verb confirms only that it arrived. That makes it easy to confuse with the grateful meaning. Acknowledging an invitation or a complaint says it was received, not that it is welcome or accepted.

The legal sense attaches to instruments such as deeds. To acknowledge one is to declare formally, typically before a notary public or similar officer, that one executed it, and that declaration gives the document validity. The act belongs to the person rather than the office: Thomas Isaac Wharton's digest of 1843 notes that a former sheriff may acknowledge a deed he executed while in office.