Thank Wank - A form of manual sex (stimulation by the hand) given in a gracious display of respect to someone who has done you a favour or otherwise indebted you.
Antonio: Can you get me a discount on this product with your trade account?
Mac: Sure man!
Antonio: Sweet! I owe you a thank wank!
Mac: Awwww yiss!

Alternatively

Antonio: Mac got me a sweet deal this weekend!
Stevo: Word son! You best get that man a thank wank!
Antionio: Way ahead of ya stevo!
Stevo: Finger lickin good!
by Loose As A Moose July 29, 2014
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