From WordNet (r) 3.0 (2006):
jest
n 1: a humorous anecdote or remark intended to provoke laughter;
"he told a very funny joke"; "he knows a million gags";
"thanks for the laugh"; "he laughed unpleasantly at his own
jest"; "even a schoolboy's jape is supposed to have some
ascertainable point" [syn: joke, gag, laugh, jest,
jape]
2: activity characterized by good humor [syn: jest, joke,
jocularity]
v 1: tell a joke; speak humorously; "He often jokes even when he
appears serious" [syn: joke, jest]
2: act in a funny or teasing way [syn: joke, jest]