Gut  —n. 1 the intestine. 2 (in pl.) The bowel or entrails. 3 (in pl.) Colloq. Personal courage and determination; perseverance. 4 slang stomach, belly. 5 (in pl.) A contents. B essence. 6 a material for violin strings etc. B material for fishing-lines made from the silk-glands of silkworms. 7 (attrib.) A instinctive (a gut reaction). B fundamental (a gut issue). —v. (-tt-) 1 remove or destroy the internal fittings of (a house etc.). 2 remove the guts of (a fish).  hate a person's guts colloq. Dislike a person intensely. [old english]