A movement (usually involuntary) of the muscles of the face, particularly of the lips, with a peculiar expression of the eyes, indicating merriment, satisfaction, or derision, and usually attended by a sonorous and interrupted expulsion of air from the lungs.
Quotations
The act of laughter, which is a sweet contraction of the muscles of the face, and a pleasant agitation of the vocal organs, is not merely, or totally within the jurisdiction of ourselves. - Sir Thomas Browne
