sweats /swɛts/noun 4phrases 1 noun[plural only]4 •(informal) A full sweatsuit; typically refers to casual, comfortable clothing; a set consisting of a sweatshirt and sweatpants, often worn for exercise or lounging. •(informal) Sweatpants. •(informal) Any illness causing copious perspiration.I have a bad case of the sweats. Do you think it's the flu? •(informal) Nervousness.Any law-abiding person gets stomach butterflies when pulled over for running a yellow light And going to traffic court can bring on a case of the sweats. — 1989 Phrases with sweats meat sweatsExcessive perspiration resulting from eating large quantities of meat.