Read the dictionary definition of jest. All definitions for this word.
1. activity characterized by good humor
2. a humorous anecdote or remark intended to provoke laughter
1. he told a very funny joke
2. he knows a million gags
3. thanks for the laugh
4. he laughed unpleasantly at his own jest
5. even a schoolboy's jape is supposed to have some ascertainable point
3. act in a funny or teasing way
4. tell a joke; speak humorously
1. He often jokes even when he appears serious
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Merriam-Webster definition of jest