A group of three males engaging in sexual acts together.
A threesome of only men.
It is referred to as A Jester's Hat due to the three long cone's that hang off of the hat, this imagery relates to the three penises involved in the act.
Nate: Dude, this party is completely ridiculous!
Dan: How so?
Nate: I walked into a room and there was A Jester's Hat!
Dan: Holy shitting thundercunt, that's crazy.
A graphic, e.g. a drawing, of a vagina.
Johnny got into trouble for scribbling a jester's hat in a very expensive schoolbook.
A sexual act performed either kneeling, squatting or sitting, surrounded by a number of standing males in a circle brandishing their penises.
The person in the middle of the circle then proceeds with oral sex on the penises, especially wanking/jerking off 2 penises at a time to emulate the shape of a Jester's hat on his or her head.
Note: Each penis refers to one of the floppy points on a jesters hat (liliripes). A minimum of 3 is required.
"That party was banging last night. Some slut was giving me and the boys a jesters hat until we jizzed all up in her face like we just opened a tin of custard."
"sup girl. how do you feel about wearing a jester's hat for me and the boys tonight?"