(informal) The spotted hyena (Crocuta crocuta); so called because of the resemblance of its call to human laughter.

A common European gull (Xema ridibundus). / An American gull (Leucophaeus atricilla); in summer the head is nearly black, the back slate color, and the five outer primaries black.

Nitrous oxide, especially when used as an anaesthetic.

A South American hawk (Herpetotheres cachinnans), so called from its notes, which resemble a shrill laughing.

(Australia, obsolete) The laughing kookaburra, Dacelo novaeguineae.

(idiomatic) An object of ridicule, someone who is publicly ridiculed; the butt of a joke.

Parodying an ostentatious expression of evilness in online written forums such as chat rooms.

A signature laugh associated with villains in films and acting, sometimes represented by muahahaha or bwahaha.

Having eyes that reflect happiness.

A deep, hearty laugh