A sexual act; specifically the act of forcing one's thumb (the most lateral digit on one's hand) into the scrotum and twirling it about in circular fashion. It is meant to be a painful experience. Audible whirring from the mouth is optional.
Shirley promised Fred pleasures of the mouth, but instead performed a dick blender upon the unsuspecting gent's scrotes. Fred should have known better when Shirley said he didn't need a cell catcher.
A: Bitch gave me a dick blender in front of er'body.
B: Whuchu do?
A: I choked a bitch.
M: Hows about a BJ?
W: Hows about a Dick Blender?
M: Up yours whore.