Etymology: Middle English sweten, from Old English swǣtan, from swāt sweat; akin to Old High German sweiz sweat, Latin sudare to sweat, Greek hidrōs sweat
Date: before 12th century
intransitive verb1 a: to excrete moisture in visible quantities through the openings of the sweat glands :perspireb: to labor or exert oneself so as to cause perspiration 2 a: to emit or exude moisture <cheese sweats in ripening>b: to gather surface moisture in beads as a result of condensation <stones sweat at night>c (1):ferment(2):putrefy 3: to undergo anxiety or mental or emotional distress <sweat through final exams> 4: to become exuded through pores or a porous surface :oozetransitive verb1: to emit or seem to emit from pores :exude 2: to manipulate or produce by hard work or drudgery 3: to get rid of or lose (weight) by or as if by sweating or being sweated 4: to make wet with perspiration 5 a: to cause to excrete moisture from the skin b: to drive hard :overworkc: to exact work from at low wages and under unfair or unhealthful conditions dslang: to give the third degree to 6: to cause to exude or lose moisture; especially: to subject (as tobacco leaves) to fermentation 7 a: to extract something valuable from by unfair or dishonest means :fleeceb: to remove particles of metal from (a coin) by abrasion 8 a: to heat (as solder) so as to melt and cause to run especially between surfaces to unite them; also: to unite by such means <sweat a pipe joint>b: to heat so as to extract an easily fusible constituent <sweat bismuth ore>c: to sauté in a covered vessel until natural juices are exuded 9slang: to worry about <doesn't sweat the small stuff — Barry McDermott>
— sweat blood: to work or worry intensely <in preparing speeches each sweats blood in his own way — Stewart Cockburn>