Are you feeling good or bad, cheerful or irritable right now? This is your mood.
Mood refers to how you feel at the present time. If you want to ask your boss for a raise, wait until he or she is in a good mood. Don't ask, though, if he or she is "in a mood" - that means the person is grumpy. If you are in the mood for something like ice cream or spicy food, you would like to have it now. Mood can also describe the attitude of a group of people or the feeling of a film, novel or piece of music.