Emily Dickinson Lexicon

KNAVE, n. [nave; Sax. cnapa or cnafa, a boy; G. knabe; D. knaap; Dan. knab; originally, a boy or young man, then a servant, and lastly a rogue.]

1. A boy; a man-child. [Obs.]
2. A servant. [Obs.] – Dryden.
3. A false deceitful fellow; a dishonest man or boy. In defiance of demonstration, knaves will continue to proselyte fools. – Ames.
4. A card with a soldier painted on it. – Hudibras.