LAUGHING

Laugh″ing (?), a. & n. from Laugh, v. i. Laughing falcon (Zoöl.), a South American hawk (Herpetotheres cachinnans); — so called from its notes, which resemble a shrill laugh. — Laughing gas (Chem.), hyponitrous oxide, or protoxide of nitrogen; — so called from the exhilaration and laughing which it sometimes produces when inhaled. It is much used as an anæsthetic agent. — Laughing goose (Zoöl.), the European white-fronted goose. — Laughing gull. (Zoöl.) (a) A common European gull (Xema ridibundus); — called also pewit, black cap, red-legged gull, and sea crow. (b) An American gull (Larus atricilla). In summer the head is nearly black, the back slate color, and the five outer primaries black. — Laughing hyena (Zoöl.), the spotted hyena. See Hyena. — Laughing jackass (Zoöl.), the great brown kingfisher (Dacelo gigas), of Australia; — called also giant kingfisher, and gogobera. — Laughing owl (Zoöl.), a peculiar owl (Sceloglaux albifacies) of New Zealand, said to be on the verge of extinction. The name alludes to its notes.