Laugh v. i. : 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.

Laugh v. i. : Fig.: To be or appear gay, cheerful, pleasant, mirthful, lively, or brilliant; to sparkle; to sport.

Laugh v. t. : To affect or influence by means of laughter or ridicule.

Laugh v. t. : To express by, or utter with, laughter; -- with out.

Laugh n. : An expression of mirth peculiar to the human species; the sound heard in laughing; laughter. See Laugh, v. i.

Example:
What are your opinions on people who Laugh under bad situations?

Taxonomy
laughter, laugh, humor, the brain, human laughter, Contagious Laughter, Health, cause laughter, theory, mechanism, Laughter Yoga, New York, Nervous laughter, free encyclopedia, Research, inconsistency, humans, danger.

Defination from the web: