The Collaborative International Dictionary of English v.0.48:
Acquaint \Ac*quaint"\, v. t. [imp. & p. p. Acquainted; p. pr.
& vb. n. Acquainting.] [OE. aqueinten, acointen, OF.
acointier, LL. adcognitare, fr. L. ad + cognitus, p. p. of
cognoscere to know; con- + noscere to know. See Quaint,
1. To furnish or give experimental knowledge of; to make
(one) to know; to make familiar; -- followed by with.
Before a man can speak on any subject, it is
necessary to be acquainted with it. --Locke.
A man of sorrows and acquainted with grief. --Isa.
2. To communicate notice to; to inform; to make cognizant; --
followed by with (formerly, also, by of), or by that,
introducing the intelligence; as, to acquaint a friend
with the particulars of an act.
Acquaint her here of my son Paris' love. --Shak.
I must acquaint you that I have received
New dated letters from Northumberland. --Shak.
3. To familiarize; to accustom. [Obs.] --Evelyn.
To be acquainted with, to be possessed of personal
knowledge of; to be cognizant of; to be more or less
familiar with; to be on terms of social intercourse with.
Syn: To inform; apprise; communicate; advise.