laugh

American Heritage® Dictionary of the English Language, Fourth Edition

1. 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.
2. v. To show or feel amusement or good humor: an experience we would laugh about later on.
3. v. To feel or express derision or contempt; mock: I had to laugh when I saw who my opponent was.
4. v. To feel a triumphant or exultant sense of well-being: You won't be laughing when the truth comes out.
5. v. To produce sounds resembling laughter: parrots laughing and chattering in the trees.
6. v. To affect or influence by laughter: laughed the speaker off the stage; laughed the proposal down.
7. v. To say with a laugh: He laughed his delight at the victory.
8. n. The act of laughing.
9. n. The sound of laughing; laughter.
10. n. Informal Something amusing, absurd, or contemptible; a joke: The solution they recommended was a laugh.
11. n. Informal Fun; amusement. Often used in the plural: went along just for laughs.
12. laugh at To treat lightly; scoff at: a daredevil who laughed at danger.
13. off To dismiss as ridiculously or laughably trivial: laughed off any suggestion that her career was over.
14. idiom. laugh out of the other side of (one's) mouth To see one's good fortune turn to bad; suffer a humbling reversal.
15. idiom. up To rejoice or exult in secret, as at another's error or defeat.

Century Dictionary and Cyclopedia

1. 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.
2. To be or appear gay; appear cheerful, pleasant, lively, or brilliant.
3. To scoff playfully; make merry; flout; jeer: with at.
4. To express laughingly; give out with jovial utterance or manner: as, he laughed his consent.
5. 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.
6. n. An expression of merriment by an explosive noise; an inarticulate expression of sudden mirth or joy.
7. 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.

Wiktionary

1. n. An expression of mirth particular to the human species; the sound heard in laughing; laughter.
2. n. Something that provokes mirth or scorn.
3. n. A fun person.
4. 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.
5. v. To be or appear cheerful, pleasant, mirthful, lively, or brilliant; to sparkle; to sport.
6. v. To make an object of laughter or ridicule; to make fun of; to deride; to mock.
7. v. To affect or influence by means of laughter or ridicule.
8. v. To express by, or utter with, laughter.

GNU Webster's 1913

1. 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.
2. v. Fig.: To be or appear gay, cheerful, pleasant, mirthful, lively, or brilliant; to sparkle; to sport.
3. v. To affect or influence by means of laughter or ridicule.
4. v. To express by, or utter with, laughter; -- with out.
5. n. An expression of mirth peculiar to the human species; the sound heard in laughing; laughter. See laugh, v. i.

WordNet 3.0

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