sound

(adjective): Healthy.
(adjective): Complete, solid, or secure.
(adjective): Having the property of soundness.
(adjective): Good; acceptable; decent.
(adjective): (of sleep) Quiet and deep. Sound asleep means sleeping peacefully, often deeply.
(adjective): Heavy; laid on with force.
(adjective): Founded in law; legal; valid; not defective.
(adverb): Soundly.
(interjection): Yes; used to show agreement or understanding, generally without much enthusiasm.