1.  a humorous utterance or action; joke.
His comment was intended to be a jest, but, unfortunately, it was taken seriously.
She began her speech with a jest that made her audience immediately warm to her.

2.  a humorous or playful manner or attitude.
They punched at each other, but it was only in jest.
The remark was made in jest, but it was offensive to many nonetheless.

See full entry