Pavlov's Dick 

a condition where, after receiving an unexpected, late night text from a girl you have fucked in the past, you get an instant boner in anticipation of whats about to go down

AJ: "Damn, i really gotta start studyin for this test"

--phone buzzes---

Text from Nikki: "heyy what r u doing??"

--PAVLOV'S DICK--

Pavlov's Dick by Genghis901 September 5, 2013

Pavlov's Dick 

A medical condition where you get an erection every time you hear a bell ring.

Stop calling me. I have Pavlov's Dick.

Pavlov's Dick by Clank Moron November 30, 2009