A slightly more sophisticated way of referring to the scrotum (ball sack). Often used in a threat of being hit in the balls.
Ted: Man you really suck at Wii.
Ralphie: You better shut up, or I'll give you a good whap to the Testes Satchel!
Bob: Why are you clutching your pants like that?
Bill: My Testes Satchel is still sore from being sacked yesterday.
A testes satchel is another way of sayin ballbag. they can be hairy, sweaty, saggy, tight etc
Can u please remove Dan's Testes Satchel from your mouth Joe you dirty teabagging homo.