sweat

(noun) salty fluid secreted by sweat glands. Synonyms: perspiration, sudor. Example: "Sweat poured off his brow."

(noun) agitation resulting from active worry. Synonyms: fret, stew, lather, swither. Examples: "Don't get in a stew." "He's in a sweat about exams."

(noun) condensation of moisture on a cold surface. Example: "The cold glasses were streaked with sweat."

(noun) use of physical or mental energy; hard work. Synonyms: effort, elbow grease, exertion, travail. Examples: "He got an a for effort." "They managed only with great exertion."

(verb) excrete perspiration through the pores in the skin. Synonyms: sudate, perspire. Example: "Exercise makes one sweat."