Huh

Interjection

 * 1) Word used to express amusement or subtle surprise.
 * Huh! I'm sure I locked it when I left.
 * 1) Word expressing doubt or confusion.
 * Huh? Where did they go?
 * 1) Word used to reinforce a question.
 * 2) Informally, used to indicate that one did not hear what was said.