Refers to the action of either playing difficult music, typically on a string instrument, or to masturbate.
"Guess what I did last night?"
"Drugs?"
"No, I was had shred on the Yoinky for hours."
1) To masturbate aggressively
2)Playing difficult music on an instrument
"Yo did you shred on the yoinky last night"
Slang for playing complex music on an instrument.
Slang for jerking off
A: Ey bro I heard you shred on the yoinky last night, we heard it from downstairs
B: Yeah man. I'm getting pretty good at guitar.
A: Nah man you were jerking off.