Thsie - adv.
The Rapidly growing affirmation, thsie, was originated in nor*cal, and simply means 'yes'. It can be used in many different contexts, mainly as a joking playful affirmation.
Rumors have it, this word has spread down the coast to Santa Barbara, and even down to LA.
Vince: yo dude, look at the gazongas on that girl, would you?