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mainline

[ meyn-lahyn, -lahyn ]
/ ˈmeɪnˌlaɪn, -ˈlaɪn /
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verb (used without object), main·lined, main·lin·ing.Slang.
to inject a narcotic, especially heroin, directly into a vein.
to use or enjoy something without restriction: to mainline on TV movies.
verb (used with object), main·lined, main·lin·ing.Slang.
to inject (a narcotic, especially heroin) directly into a vein.
to use, enjoy, or imbibe (something) without restriction: mainlining coffee all day long.
adjective
having a principal, established, or widely accepted position; major; mainstream: the membership of mainline churches.
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Origin of mainline

1935–40, Americanism; v., adj. use of main line

Other definitions for mainline (2 of 3)

main line

noun
a principal line or route of a railroad, as contrasted with a branch or secondary one.
a principal highway.
Slang.
  1. a prominent and readily accessible vein of the body that may be used for a narcotic's injection.
  2. the act of mainlining.

Origin of main line

First recorded in 1835–45

Other definitions for mainline (3 of 3)

Main Line

noun
a fashionable residential district west of Philadelphia.
any fashionable district where socially prominent people live.

OTHER WORDS FROM Main Line

Main-Line, adjectiveMain-Liner, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2022

How to use mainline in a sentence

British Dictionary definitions for mainline

main line

noun
railways
  1. the trunk route between two points, usually fed by branch lines
  2. (as modifier)a main-line station
US a main road
verb mainline
(intr) slang to inject a drug into a vein
adjective mainline
having an important position, esp having responsibility for the main areas of activity

Derived forms of main line

mainliner, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
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