Origin and history of suppressive

late 14c. (implied in verbal noun suppressing) "be burdensome," also "quell, cause to cease;" from Latin suppressus, past participle of supprimere "press down, stop, hold back, check, stifle," from assimilated form of sub "below, under" (see sub-) + premere "to press, hold fast, cover, crowd, compress" (from PIE root *per- (4) "to strike").

by 1520s of feelings, desires, etc., "put down, prevent from expression by force." The sense of "prevent or prohibit the circulation of, withhold from disclosure" is from 1550s. The medical sense of "hinder the flow or discharge" is from 1620s. Related: Suppressed; suppressing.

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).