1520s, "obtain as profit," from French gagner, from Old French gaaignier "to earn, gain; trade; capture, win," also "work in the fields, cultivate land," from Frankish *waidanjan "hunt, forage," also "graze, pasture," from Proto-Germanic *waithanjan "to hunt, plunder," from *waithjo- "pursuit, hunting" (source also of Old English waþ "hunting," German Weide "pasture, pasturage," Old Norse veiðr "hunting, fishing, catch of fish").
This is from PIE root *weie- "to go after, strive after, pursue vigorously, desire," with noun derivatives indicating "force, power" (related to *wi-ro- "man;" see virile). Cognates include Sanskrit padavi- "track, path, trail," veti- "follows, strives, leads, drives;" Avestan vateiti "follows, hunts;" Greek hiemai "move oneself forward, strive, desire;" Lithuanian vyti "to chase, pursue;" Old Norse veiðr "chase, hunting, fishing;" Old English OE wað "a chase, hunt."
Meaning "obtain by effort or striving" is from 1540s; intransitive sense of "profit, make gain" is from 1570s. Meaning "arrive at" is from c. 1600. Of timepieces by 1861. Related: Gained; gaining. To gain on "advance nearer" is from 1719. To gain ground (1620s) was originally military.
c. 1300, "an inquest, a judicial inquiry;" early 14c., "a search for something, the act of seeking, pursuit" (especially in reference to hounds seeking game in the hunt), from Old French queste "search, quest, chase, hunt, pursuit; inquest, inquiry" (12c., Modern French quête), properly "the act of seeking," and directly from Medieval Latin questa "search, inquiry," alteration of Latin quaesitus (fem. quaesita) "sought-out, select," past participle of quaerere "seek, gain, ask" (see query (n.)).
The medieval romance sense of "adventure undertaken by a knight" (especially the search for the Grail) is attested from late 14c. Chaucer has questmonger (late 14c.), "one who profits from an unjust action at law."
French chassé "chase, chasing," past participle of chasser "to chase, hunt" (see chase (v.)), borrowed 19c. into English in a variety of senses and expressions, such as "chaser" (in the drinking sense), short for chasse-café, literally "coffee-chaser." Also as a dance step (1867).
"pertaining to life," 1847, also biotical (1847), from Latin bioticus, from Greek biotikos "pertaining to life," from bios "life," from PIE root *gwei- "to live." Biotic factor was in use by 1907. Related: Biotical. Biotics "science of vital functions and manifestations; powers and qualities peculiar to living organisms" (T. Sterry Hunt) is from 1882.
1570s, "weasel-like animal of Egypt," from Latin ichneumon, from Greek ikhneumon "ichneumon," literally "searcher, tracker," perhaps so called because it hunts crocodile eggs, from ikhneuein "hunt for, track," from ikhnos "a track, footstep, trace, clue," which is of unknown origin. Used by Aristotle for a species of wasp that hunts spiders (a sense attested in English from 1650s).
"worthless person," 1946, British slang, a southern variant of Scottish get "illegitimate child, brat," which is attested by 1706 ("Gregor Burgess protested against the said Allane that called him a witch gyt or bratt"), according to "Dictionary of the Scots Language"); related to beget on the notion of "what is got." Scots get, gyt, geitt, etc. also can be an affectionate term for a child.