Dictionary definition of 'damn' damn = to condemn someone. The word is also used to express hatred or dislike for something. v. damned, damning, damns v.tr. 1. To pronounce an adverse judgment upon. 2. To bring about the failure of; ruin. 3. To condemn as harmful, illegal, or immoral: a cleric who damned gambling and strong drink. 4. To condemn to everlasting punishment or a similar fate; doom. 5. To swear at. v.intr. To swear; curse. interj. Used to express anger, irritation, contempt, or disappointment. n. 1. The saying of "damn" as a curse. 2. Informal The least valuable bit; a jot: not worth a damn. adv. & adj. Damned. Idiom: damn well Without any doubt; positively: I am damn well going to file charges against him.

It's a swear word. Use it when you're angry.