(verb) The process of injesting alcohol (normally) by means of funneling/feeding the liquids through a pipe (or more commonly used, a ~ 1-2 in. diameter hose) directly into the stomach.
The object of pipelining is to bypass the gag reflex to give worry free injection of hard liquor.
Works best with 100 proof alcohol.
May acceptably be called 'lining, if you are deemed cool enough to do so.
"I had an awesome time pipelining with you guys last night, you guys are all so cool..."
"Hey bro, lets do some 'lining"
"Kraven and Jrio are definately the most hardcore pipeliners in the world"