Entries linking to sweat-bee
Old English swat "perspiration, moisture exuded from the skin," also "labor, that which causes sweat," from Proto-Germanic *swaitaz "sweat" (source also of Old Saxon, Old Frisian swet, Old Norse sveiti, Danish sved "sweat," Swedish svett, Middle Dutch sweet, Dutch zweet, Old High German sweiz, German Schweiß), from PIE *sweid- (2) "to sweat" (source also of Sanskrit svedah "sweat," Avestan xvaeda- "sweat," Greek hidros "sweat, perspiration," Latin sudor, Lettish swiedri, Welsh chwys "sweat").
A widespread set of Slavic words (Polish, Russian pot "sweat") is from Old Church Slavonic potu, related to peku "heat," cognate with Latin coquere.
The Old English noun became Middle English swote, but later altered to the current form under the influence of the verb. Sweat of (one's) brow as a symbol of toil is from Genesis iii.19. Sweat equity is from 1968. Colloquial no sweat "no problem" is attested by 1953, said to be originally U.S. military jargon from the Korean War.
The universal and all-inclusive word today is "sweat." It covers just about everything: "no sweat" means no trouble, no cause for worry, nothing fouled up, don't fret. "It's a sweat" means a patrol looks tough, or an order to dig some more trench is an outrage, or simply that everything is messed up as usual. ["A Frontline Picture No Camera Could Get," Life magazine, March 16, 1953]
stinging insect of the genus Apis, living in societies under a queen and producing wax and honey, Old English beo "bee," from Proto-Germanic *bion (source also of Old Norse by, Old High German bia, Middle Dutch bie), from PIE root *bhei- "bee."
Used metaphorically for "busy worker" since 1530s. Sense of "meeting of neighbors to unite their labor for the benefit of one of their number," 1769, American English, probably is from comparison to the combined labor and social activity of the insect; this was extended to other senses (such as spelling bee, attested by 1809; Raising-bee (1814) for building construction; quilting bee (1824, see quilt (v.)); logging-bee for a log-rolling; paring-bee for preparing harvested apples; also hanging bee "a lynching").
To have a bee in (one's) bonnet (1825), said of one who is harebrained or has an intense new notion or fancy, is said in Jamieson to be Scottish, perhaps from earlier expressions such as head full of bees (1510s), denoting mad mental activity.