late 14c., "to raze, destroy, overthrow, undermine, overturn," from Old French subvertir "overthrow, destroy" (13c.), or directly from Latin subvertere "to turn upside down, overturn, overthrow," from sub "under" (see sub-) + vertere "to turn, turn back, be turned; convert, transform, translate; be changed" (from PIE root *wer- (2) "to turn, bend"). Related: Subverted; subverting.
word-forming element making adjectives from verbs, meaning "pertaining to, tending to; doing, serving to do," in some cases from Old French -if, but usually directly from Latin adjectival suffix -ivus (source also of Italian and Spanish -ivo). In some words borrowed from French at an early date it has been reduced to -y (as in hasty, tardy).
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Harper, D. (n.d.). Etymology of subversive. Online Etymology Dictionary. Retrieved $(datetime), from https://www.etymonline.com/word/subversive