teamster n.

Old English team "descendant, family, race, line; child-bearing, brood; company, band; set of draft animals yoked together," from Proto-Germanic *tau(h)maz (source also of Old Norse taumr, Old Frisian tam "bridle; progeny, line of descent," Dutch toom, Old High German zoum, German Zaum "bridle"), probably literally "that which draws," from PIE *douk-mo-, from root *deuk- "to lead."

Applied in Old English to groups of persons working together for some purpose, especially "group of people acting together to bring suit;" the modern sense of "persons associated in some joint action" is from 1520s. Team spirit is recorded from 1928. Team player attested from 1886, originally in baseball.

Old English -istre, from Proto-Germanic *-istrijon, feminine agent suffix used as the equivalent of masculine -ere (see -er (1)). Also used in Middle English to form nouns of action (meaning "a person who ...") without regard for gender.

The genderless agent noun use apparently was a broader application of the original feminine suffix, beginning in the north of England, but linguists disagree over whether this indicates female domination of weaving and baking trades, as represented in surnames such as Webster, Baxter, Brewster, etc. (though modern spinster probably carries an originally female ending).

Also compare whitester "one who bleaches cloth;" kempster (c. 1400; Halliwell has it as kembster) "woman who cleans wool." Chaucer ("Merchant's Tale") has chidester "an angry woman" (the 17c. had scoldster). Also compare Middle English shepster (late 14c.) "dressmaker, female cutter-out," literally "shapester," sleestere (mid-15c.) "murderess, female killer" ("slay-ster"). Sewster "seamstress" (Middle English seuestre, late 13c. as a surname, also used of men) is still in Jonson but was obsolete or provincial after 17c. In Modern English, the suffix has been productive in forming derivative nouns (gamester, roadster, punster, rodster "angler," etc.).