Tap
water consumed on a night out as a substitute for alcohol, usually
drunk on it's own but sometimes
drunk alongside alcoholic beverages.
Guy A: Sup dude, what you
drinking there?
Guy B: It's a happy tappy dude.
Guy A: Man I'm thirsty, but I don't want to get
drunk.
Guy B: Hey try this, it's a happy tappy.
Guy A: Whoa, this is super refreshing!
Guy B: I
know right!