To express certain emotions, especially mirth or delight, by a series of spontaneous, usually unarticulated sounds often accompanied by corresponding facial and bodily movements. To show or feel amusement or good humor: an experience we would laugh about later on. To feel or express derision or contempt; mock: I had to laugh when I saw who my opponent was. To feel a triumphant or exultant sense of well-being: You won't be laughing when the truth comes out. To produce sounds resembling laughter: parrots laughing and chattering in the trees. To affect or influence by laughter: laughed the speaker off the stage; laughed the proposal down. To say with a laugh: He laughed his delight at the victory. The act of laughing. The sound of laughing; laughter. Informal Something amusing, absurd, or contemptible; a joke: The solution they recommended was a laugh. Informal Fun; amusement. Often used in the plural: went along just for laughs. laugh at To treat lightly; scoff at: a daredevil who laughed at danger. off To dismiss as ridiculously or laughably trivial: laughed off any suggestion that her career was over. laugh out of the other side of (one's) mouth To see one's good fortune turn to bad; suffer a humbling reversal. up To rejoice or exult in secret, as at another's error or defeat.