Emily Dickinson Lexicon

dont (don't), v. [contraction form; see do, v. and not, adv.]

1. Do not; [auxiliary for a negated action.]
2. Doesn't; does not; [colloquial auxiliary for a negated action in the third person.]
3. Phrase. “dont you know”: do you not know? [negated question for affirmative emphasis] surely you know; certainly you do know.