Tongue-in-cheek

[Tanya Shivari]

Tongue-in-cheek is a term used to refer to humor in which a statement is not meant to be taken seriously, but its lack of seriousness is subtle.
Nonetheless beware of jackasses trying to use it as an out-of-jail card sometimes when they fuck up and say some stupid they really meant.

[Raeanne Dimick]

cleverly amusing in tone

[EfrainaLign]

not intended seriously; jocular or humorous

[Thu Thi Le]

in a bantering fashion