jest
/ˈjest/
noun
a joking or mocking remark
prank
a ludicrous circumstance or incident
a clever jest
verb
to make jokes or jests : to say things intended to be humorous
"What's it like to design a building and have an apartment in it and have your name on it?" the architect asks, jesting, with his typically irrepressible energy. "It's like a hat trick."
idiom
as a joke
I didn't mean to upset you; I only said it in jest.