acquainted (adj.)youdaoicibaDictYouDict[acquainted 词源字典]
early 13c., "personally known;" past participle adjective from acquaint (v.). Of skills, situations, etc., from late 15c.
I have been one acquainted with the night.
I have walked out in rain —- and back in rain.
I have outwalked the furthest city light.

[Robert Frost, from "Acquainted with the Night"]
[acquainted etymology, acquainted origin, 英语词源]