JOKE, noun [Latin jocus.]
1. A jest; something said for the sake of exciting a laugh; something witty or sportive; raillery. A jealous person will rarely bear a joke
2. An illusion; something not real, or to no purpose.
Inclose whole downs in walls, 'tis all a joke!
In joke in jest; for the sake of raising a laugh; not in earnest.
JOKE, verb intransitive [Latin jocor.] To jest; to be merry in words or actions.
JOKE, verb transitive To rally; to cast jokes at; to make merry with.