the term is relatively new. it refers to the current state of (political) affairs in the united states (but probably doesn't preclude the emerging political model in many european countries...). it basically refers to the ever-widening ideological gap that exists between the voters and those receiving the votes. a political model that underscores a voter's influence. this term was coined by gore vidal.
that ours is a post democracy can be evidenced by last month's poor voter turnout.
purely and simply an alternative to "fuck". the term most likely came out of the austin, tx area in the mid 90's when austin uber alles experienced its new sexual revolution and casual sex became commonplace. fifteen, then, probably refers to the amount of time a good casual fuck takes- 15 minutes. perhaps the reference is to amount of positions.
we got so horny that we decided to fifteen right there on her parents bed.
gbt is an acronym for Gravity Bong Toke. it is the preferred method of ingestion among many potheads. typically, the user will position a bowl on the mouthpiece of an empty 2-liter bottle of pepsi with the bottom cut off. whilst burning the tweeds in the bowl the user slowly lifts the 2-liter from a container of water which creates a pressure and simulates the sucking of the bowl. the empty 2-liter quickly becomes quite full with milky smoke. the user then takes one long exhale, lifts the bowl from the mouth of the 2-liter and proceeds to incapicitate his or herself for the next 3 hours by enhaling the toxic smoke.