adj
mainline
MAYN-lyn
adj
1
Belonging to the principal, standard, or most widely accepted version of something.
"The band moved from underground clubs into mainline radio play."
verb
1
To inject a drug directly into a vein.
"The character in the film is shown mainlining heroin."
How to Use Mainline
Learner’s notesIn plain EnglishAs an adjective, "standard" or "mainstream"; as a verb, injecting a drug straight into a vein.
When to use it
The drug-injection sense is informal and appears mostly in reference to hard drug use.
Word Forms
mainlined past tense, mainlines singular
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The band moved from underground clubs into _____ radio play.
Etymology
From main + line.