Pronunciation: (kum-plān'),[key] —v.i. 1. to express dissatisfaction, pain, uneasiness, censure, resentment, or grief; find fault: He complained constantly about the noise in the corridor. 2. to tell of one's pains, ailments, etc.: to complain of a backache. 3. to make a formal accusation: If you think you've been swindled, complain to the police.