Difficult to deal with or control: a problem child.
A question to be considered, solved, or answered: math problems; the problem of how to arrange transportation.
A situation, matter, or person that presents perplexity or difficulty: was having problems breathing; considered the main problem to be his boss. See Usage Note at dilemma.
A misgiving, objection, or complaint: I have a problem with his cynicism.
Dealing with a moral or social problem: a problem play.
no problem Used to express confirmation of or compliance with a request.