Meanings of japery in English

The She-Bear gave her grudging assent, deaf to the japery in his tone.

Yet parting mist, which impressed no one, most especially not the Knife, had a cost far above such japery.

Thereafter, one shinned up the ladder, on post-prandial japery intent, another beat the devil's tattoo, a third writhed cachinnatory.

How the Australian barracking of Stuart Broad felt clever and affectionate, the witty japery of an intelligent and respected rival?

Despite the japery of Newsround theme tune samples and bagpipes, this good humour is mined more from their ambitious experimentation than anything else.