ken (v.)

"to know, understand, take cognizance of," a word surviving mainly in Scottish and northern England dialect, from Middle English kennen, "make known; give instruction to; be aware, know, have knowledge of, know how to; recognize by sight; see, catch sight of," a very common verb, from Old English cennan "make known, declare, acknowledge" (in late Old English also "to know"), originally "cause to know, make to know," causative of cunnan "to become acquainted with, to know" (see can (v.)). Cognate with German kennen, Danish kjende, Swedish känna. Related: Kenned; kenning.

1550s, "cognizance, intellectual view;" 1580s in a physical sense, "range of sight;" from ken (v.), in the second sense perhaps via kenning (n.2) in the same sense in nautical use; both from PIE root *gno- "to know."

"house used as a meeting place by thieves or other disreputable characters," 1560s, vagabonds' slang, probably a shortening of kennel (n.).