Complain is a verb that means to express dissatisfaction, annoyance, or resentment about something.
Common usage examples:
1. "She complained about the poor service at the restaurant."
2. "He's always complaining that he doesn't have enough time."
3. "You can complain to the manager if you're not satisfied."
Related expressions:
- Complaint (noun): a formal expression of dissatisfaction
- Complainer (noun): a person who complains frequently