"that causes annoyance," 1707, present-participle adjective from irritate (v.). Related: Irritatingly. Earlier adjective forms were irritative (1680s), irritatory (1650s).
Entries linking to irritating
irritate v.
1530s, "stimulate to action, rouse, incite," from Latin irritatus, past participle of irritare "excite, provoke, annoy;" according to de Vaan, probably a verb from Proto-Italic *rito- "stirred," from the same PIE root that produced English run (v.). Meaning "annoy, make impatient" in English is from 1590s. The earlier verb in English was irrite (mid-15c.), from Old French irriter. Related: Irritated; irritating.