The verb complain has 2 senses (first 1 from tagged texts)
1. (29) complain, kick, plain, sound off, quetch, kvetch -- (express complaints, discontent, displeasure, or unhappiness; "My mother complains all day"; "She has a lot to kick about")
2. complain -- (make a formal accusation; bring a formal charge; "The plaintiff's lawyer complained that he defendant had physically abused his client")