"seize forcibly or roughly," 1580s, from Middle Dutch or Middle Low German grabben "to grab," from Proto-Germanic *grab-, *grap- (source also of Old English græppian "to seize," Old Saxon garva, Old High German garba "sheaf," literally "that which is gathered up together"), from PIE *ghrebh- (1) "to seize, reach" (source also of Sanskrit grbhnati "seizes," Old Persian grab- "seize" as possession or prisoner, Old Church Slavonic grabiti "to seize, rob," Lithuanian grėbti "to rake"). Sense of "to get by unscrupulous methods" was reinforced by grab game, a kind of swindle, attested from 1846. Related: Grabbed; grabbing.
Indian form of passive resistance, 1920, in writings of Gandhi, from Sanskrit satyagraha "insistence on truth," from satya "truth, truthfulness" (from sat- "existing, true, virtuous," from PIE root *es- "to be") + agraha "pertinacity," from gṛbhṇāti, gṛhṇāti "he seizes" (from PIE root *ghrebh- (1) "to seize, reach;" see grab (v.)). Related: Satyagrahi.
Perhaps the English word originally is from a derivative of Old French garbe/jarbe "sheaf of wheat, bundle of sheaves," though the sense connection is difficult. This word is from Proto-Germanic *garba- (source also of Dutch garf, German garbe "sheaf"), from PIE *ghrebh- (1) "to seize, reach" (see grab (v.)).
"In modern American usage garbage is generally restricted to mean kitchen and vegetable wastes" [Craigie]. Used figuratively for "worthless, offensive stuff" from 1590s. Garbage can is from 1901. Garbage collector "trash man" is from 1872; Australian shortening garbo attested from 1953. Garbology "study of waste as a social science" is by 1976; garbologist is from 1965.