WordNet (r) 3.0 (2006):
heat up v 1: gain heat or get hot; "The room heated up quickly" [syn: heat, hot up, heat up] [ant: chill, cool, cool down] 2: make hot or hotter; "the sun heats the oceans"; "heat the water on the stove" [syn: heat, heat up] [ant: chill, cool, cool down] 3: make more intense; "Emotions were screwed up" [syn: heat up, hot up, screw up]