What is Mainlining?
1.
the intravenous injection of a drug. which means using a needle to get a drug into your vein, to absorb it through your bloodstream. a lot of drugs can be taken this way, the most commonly associated drug being
Layne accidentally overdosed by mainlining heroin.
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2.
the act of taking internet lingo and applying it to real life conversation
matt: I walked by a group of kids taking a test and said, "fucking scrubs."
joel: dude, you were totally mainlining.
See