thawEnglishOxford American Thesaurusthaw verb 1 the ice was beginning to thaw: melt, unfreeze, soften, liquefy, dissolve; North American unthaw. ▷antonyms freeze, solidify. 2 a frozen turkey may take up to two days to thaw: defrost. ▷antonyms freeze. 3 since I've been here, he's begun to thaw: become friendlier, become more genial, become more sociable, loosen up, relax, become more relaxed.