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mainline

[ meyn-lahyn, -lahyn ]
/ ˈmeɪnˌlaɪn, -ˈlaɪn /
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See synonyms for mainline on Thesaurus.com
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

Words nearby mainline

main idea, mainland, mainland China, mainlander, mainland Japan, mainline, mainliner, mainly, main man, main market, mainmast

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. 2023

Words related to mainline

dominant, key, leading, main, major, outstanding, paramount, predominant, preeminent, primary, prime, prominent, vaccinate, arch, capital, cardinal, champion, chief, essential, first

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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