ir·ri·tate / ˈiriˌtāt/ • v. [tr.] make (someone) annoyed, impatient, or angry: his tone irritated her | [intr.] his voice tends to irritate | [as adj.] (irritating) highly irritating remarks. ∎ cause inflammation or other discomfort in (a part of the body). ∎ Biol. stimulate (an organism, cell, or organ) to produce an active response.DERIVATIVES: ir·ri·tat·ed·ly adv.ir·ri·tat·ing·ly adv.ir·ri·ta·tive / -ˌtātiv/ adj.ir·ri·ta·tor / -ˌtātər/ n.