Entry 1 sense Webster, 1913 Comatose /kōm'-ət-ōsˌ/ · Co·ma·tose · IPA /ˈkoʊ.məˌtoʊs/ 01 a. Relating to, or resembling, coma; drowsy; lethargic; as, comatose sleep; comatose fever. 1. Relating to, or resembling, coma; drowsy; lethargic; as, comatose sleep; comatose fever.