What is Mainline?
1.
To inject a drug, usually heroin, into a vein. Also used to refer to the drug itself.
"That chick was mainlining heroin daily till she OD'd."
From Queensryche - Operation Mindcrime:
"Had a habit doing mainline
Watch the dragon burn
No regrets, you've got no goals
Nothing more to learn"
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2.
A person's main significant other, even though they may be dating several people at once.
"I got a lot of chicks, I ain't gotta lie. But you keep it real, so you my mainline." - Ray Vicks
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3.
To watch a large amount of a geeky television show, episode after episode, for a long period of time. A season of Buffy in two days, for example.
Similar to marathoning movies or chain smoking, but more geeky.
"I just mainlined the first 3 seasons of Angel"
"I'm going to go home and mainline the LOTR movies."
"Wheres Ferg at?"
"Oh, hes at home, sitting in the dark, mainlining Simpsons episodes"
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