It all started from Spock's way of saying "sens-ors" Evolved into the drinking game, across all series & movies, anytime some says "sensors" on screen, take a shot, or take a drink. *Since the wife and I watch Trek each night before bed, it's usually a swig of water. Still fun.
My sister lives Tuvok's pronunciation of the word, and we've incorporated it into our own hypothetical drinking game. But a Star Trek drinking game should be played with Romulan Ale or Blood Wine.