means A man granted honorary rank by a monarch (historically a mounted warrior in armor, today an honorific like 'Sir'), or the chess piece that moves in an L and leaps over others.

from From Old English 'cniht,' which originally meant simply a boy or young servant — no horse, no honor, just a lad doing as he's told. Over the centuries the word climbed the social ladder, from servant to military attendant to armored noble warrior, a rare case of a word getting promoted. It's related to German 'Knecht,' which kept the humbler meaning of farmhand or servant. The silent 'k' is a fossil: English speakers once actually pronounced that opening 'k-n' sound, before it quietly fell out of fashion and left the letter stranded.