Answer: tongueincheek

AnswerCrossword Clue
TONGUEINCHEEK

Insincere

TONGUEINCHEEK

Facetious

TONGUEINCHEEK

Not serious

TONGUEINCHEEK
Like a whimsical remark
TONGUEINCHEEK
With whimsical irony
TONGUEINCHEEKAttitude of whimsical disbelief.
TONGUEINCHEEKWithout sincerity.
TONGUEINCHEEKWith irony or whimsy.