laugh

from The American Heritage® Dictionary of the English Language, 4th Edition

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

from Wiktionary, Creative Commons Attribution/Share-Alike License

• n. An expression of mirth particular to the human species; the sound heard in laughing; laughter.
• n. Something that provokes mirth or scorn.
• n. A fun person.
• v. To show mirth, satisfaction, or derision, by peculiar movement of the muscles of the face, particularly of the mouth, causing a lighting up of the face and eyes, and usually accompanied by the emission of explosive or chuckling sounds from the chest and throat; to indulge in laughter.
• v. To be or appear cheerful, pleasant, mirthful, lively, or brilliant; to sparkle; to sport.
• v. To make an object of laughter or ridicule; to make fun of; to deride; to mock.
• v. To affect or influence by means of laughter or ridicule.
• v. To express by, or utter with, laughter.

from the GNU version of the Collaborative International Dictionary of English

• n. An expression of mirth peculiar to the human species; the sound heard in laughing; laughter. See laugh, v. i.
• intransitive v. To show mirth, satisfaction, or derision, by peculiar movement of the muscles of the face, particularly of the mouth, causing a lighting up of the face and eyes, and usually accompanied by the emission of explosive or chuckling sounds from the chest and throat; to indulge in laughter.
• intransitive v. Fig.: To be or appear gay, cheerful, pleasant, mirthful, lively, or brilliant; to sparkle; to sport.
• transitive v. To affect or influence by means of laughter or ridicule.
• transitive v. To express by, or utter with, laughter; -- with out.

from The Century Dictionary and Cyclopedia

• To express mirth or joy by an explosive inarticulate sound of the voice and a peculiar facial distortion; make a convulsive or chuckling noise excited by sudden merriment or pleasure.
• To be or appear gay; appear cheerful, pleasant, lively, or brilliant.
• To scoff playfully; make merry; flout; jeer: with at.
• To express laughingly; give out with jovial utterance or manner: as, he laughed his consent.
• To affect in some way by laughter, or a laughing manner; act upon by exercise of risibility: as, to laugh one's self sick or into convulsions; to laugh one out of countenance.
• n. An expression of merriment by an explosive noise; an inarticulate expression of sudden mirth or joy.
• n. Mirth or merriment, particularly at the expense of some person or thing; ridicule: used with the definite article: as, the laugh was turned against him.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• n. a humorous anecdote or remark intended to provoke laughter
• n. a facial expression characteristic of a person laughing
• v. produce laughter
• n. the sound of laughing