Recieving Head from an elderly. Be it man or women, A greyskull is just that - get'n a grey skull down on you.
"man i LOVE me a good GMILF, and when the night ends with a Greyskull, that makes it all the more better"
A term used to express a strong desire to have sexual acts with another. Refers to TV cartoon he-Man and the power of greyskull, a clearly mighty force to be reckoned with.
I want to greyskull that lady.
I want to fist you with the power of greyskull