Mind-shaft
When a fellow chap uses his male genital organ to think, rather than his head.
"Look at you John!. She took half of your equitable estate, your kids, and the only thing she gave you is god damn squirrel AIDS, and hepatitis A through Z. Really naive!!! You should stop thinking with your mind-shaft and start using that big melon of yours!".
Mind-shaft
When a fellow chap thinks with his male genital organ rather than his head
"Look at you John, she took half of your equitable estate, your kinds, and all she gave you is god damn squirrel AIDS, and hepatitis A through Z! Really naive; you should stop thinking with your mind-shaft and start using that big melon of yours."