1520s, "make heavy, burden down," from Latin aggravatus, past participle of aggravare "to render more troublesome," literally "to make heavy or heavier, add to the weight of," from ad "to" (see ad-) + gravare "weigh down," from gravis "heavy" (from PIE root *gwere- (1) "heavy"). The literal sense in English has become obsolete; meaning "to make a bad thing worse" is from 1590s; colloquial sense "exasperate, annoy" is from 1610s. The earlier English verb was aggrege "make heavier or more burdensome; make more oppressive; increase, intensify" (late 14c.), from Old French agreger.
To aggravate has properly only one meaning — to make (an evil) worse or more serious. [Fowler]
It forms all or part of: aggravate; aggravation; aggrieve; bar (n.4) "unit of pressure;" bariatric; baritone; barium; barometer; blitzkrieg; brig; brigade; brigand; brigantine; brio; brut; brute; charivari; gravamen; grave (adj.); gravid; gravimeter; gravitate; gravity; grief; grieve; kriegspiel; guru; hyperbaric; isobar; quern; sitzkrieg.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit guruh "heavy, weighty, venerable;" Greek baros "weight," barys "heavy in weight," often with the notion of "strength, force;" Latin gravis, "heavy, ponderous, burdensome, loaded; pregnant;" Old English cweorn "quern;" Gothic kaurus "heavy;" Lettish gruts "heavy."
1640s, "exert weight; move downward" (obsolete), from Modern Latin gravitare (16c. in scientific writing), from Latin gravitas "heaviness, weight," from gravis "heavy" (from PIE root *gwere- (1) "heavy"). Meaning "be affected by gravity" is from 1690s. Figurative sense "be strongly attracted to, have a natural tendency toward" is from 1670s. Related: Gravitated; gravitating. The classical Latin verb was gravare "to make heavy, burden, oppress, aggravate."