Aggressive fibromatoses, also known as desmoid tumors, are benign but locally invasive tumors that can cause significant morbidity and functional impairment. Antonyms for aggressive fibromatoses could include noninvasive, benign, harmless, or mild. These terms describe tumors that do not invade adjacent tissues, do not lead to significant functional impairment or morbidity, and do not need aggressive treatment. While there are no true antonyms for aggressive fibromatoses, the opposite of a locally invasive tumor is one that does not invade adjacent tissues or cause significant functional impairment. Thus, benign, noninvasive, harmless, or mild could be considered antonyms for aggressive fibromatoses.