Entry 1 sense Webster, 1913 Complainer /(kŏm*plān"ẽr)/ · Com·plain·er · IPA /kəmˈpleɪnɚ/ 01 n. One who complains or laments; one who finds fault; a murmurer. 1. One who complains or laments; one who finds fault; a murmurer. “Speechless complainer, I will learn thy thought.” — Shak.