Definition of "Joke" :
noun: a ludicrous or grotesque act done for fun and amusement
noun: activity characterized by good humor
noun: a triviality not to be taken seriously
"I regarded his campaign for mayor as a joke."
noun: a humorous anecdote or remark intended to provoke laughter
"He told a very funny joke."
verb: act in a funny or teasing way
verb: tell a joke; speak humorously
"He often jokes even when he appears serious."