mainlined; mainlining; mainlines
Definition of mainline
(Entry 1 of 3)
slang
: to take by or as if by injecting into a principal vein
slang
: to mainline a narcotic drug
mainline
adjectiveDefinition of mainline (Entry 2 of 3)
: being part of an established group
also
: being in the mainstream
main line
nounDefinition of main line (Entry 3 of 3)
1
: a principal highway or railroad line
2
slang
: a principal vein of the circulatory system
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Merriam-Webster unabridged
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Time Traveler for mainline
The first known use of mainline was in 1841
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