An involuntary yet pleasant physical manifestation affecting one's facial features as a result of the amused, giddy feeling one experiences when accelerating while driving a Tesla vehicle.

A reaction to the magic of intention and simultaneous vehicular feedback: hitting the gas pedal and going 0 to 60 m/hr (or 100 km/hr) in 3 seconds.

Feeling like you're in warp drive and loving it.
He couldn't wipe that Tesla grin off his face even after the car came to a complete stop.
by izfo May 2, 2016
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