mainline

verb
main·line | \ ˈmān-ˌlīn \
mainlined; mainlining; mainlines

Definition of mainline 

(Entry 1 of 3)

transitive verb

slang : to take by or as if by injecting into a principal vein

intransitive verb

slang : to mainline a narcotic drug

mainline

adjective

Definition of mainline (Entry 2 of 3)

: being part of an established group also : being in the mainstream

main line

noun

Definition of main line (Entry 3 of 3)

1 : a principal highway or railroad line

2 slang : a principal vein of the circulatory system

Examples of mainline in a Sentence

Verb

His addiction grew worse when he began mainlining.

Recent Examples on the Web: Verb

That both doctors vouched for the health of a man who mainlines McDonald's and likes steak and meatloaf is incredible. Z. Byron Wolf, CNN, "The surreal tales of Trump's 2 former doctors," 1 May 2018 And no one seemed to be given pause by the fact that the brand’s most famous son had mainlined a fatal speedball just across the street. Benjamin Wallace, HWD, "Can Anyone Repair National Lampoon’s Devastated Brand?," 1 May 2017 Before any stars turned up to rehearse for Sunday's ceremony, crew members were busy putting the finishing touches on the elaborate production, rushing around wearing headsets and mainlining coffee from craft services. Amy Kaufman, latimes.com, "The Oscars turn 90, and the production team leaves no room for error ... this time," 2 Mar. 2018 Working with producer Greg Kurstin—a pop wizard whose credits include Adele, Kelly Clarkson, Sia, Ellie Goulding, and Lily Allen—Beck basically mainlined the top of the charts. Matt Miller, Esquire, "Beck's New Album Is Perfect for a Really Weird Car Commercial," 13 Oct. 2017 There are rappers who mainline the aesthetic and vibrating energy of punk. Jon Caramanica, New York Times, "Lil Uzi Vert and a Generation of Rap Stars Looking Beyond Hip-Hop," 1 Sep. 2017 And no one seemed to be given pause by the fact that the brand’s most famous son had mainlined a fatal speedball just across the street. Benjamin Wallace, HWD, "Can Anyone Repair National Lampoon’s Devastated Brand?," 19 May 2017 Watching Game of Thrones now feels like mainlining a bunch of CW shows like Arrow or Vampire Diaries—or even, sometimes, Jane the Virgin. Annalee Newitz, Ars Technica, "Game of Thrones has become a CW show," 28 Aug. 2017 Soon, us kids were mainlining the hard stuff - Eugene O'Neill and Tennessee Williams - and getting high on Sam Shepard. Andrea Simakis, cleveland.com, "Mamai Theatre Company, with an assist from Thornton Wilder, breathes new life into 'A Doll's House.' (Review)," 24 Aug. 2017

Recent Examples on the Web: Adjective

There would then be 32 registered Democrats to be seated in the 63-member Senate (eight IDC members, 23 mainline Democratic members and one Simcha Felder). Chris Cillizza, CNN, "Here's exactly how much trouble Cynthia Nixon can cause for Andrew Cuomo," 20 Mar. 2018 Many mainline carriers are increasing their own recruiting and training efforts. New York Times, "More Jobs Will Be Cleared for Takeoff. Aspiring Pilots Are Ready.," 27 May 2018 The goal is to experience music from around the world, not mainline Justin Bieber for a weekend. Sarah Bahr, Indianapolis Star, "Ultimate Indiana bucket list: 50+ things to do in Indianapolis and around the state," 11 July 2018 Installing redundant power supply system. — Reconstructing 25,000 linear feet of mainline track. Jennifer Fenn Lefferts, BostonGlobe.com, "Green Line’s D branch slated for upgrades," 28 June 2018 Nevertheless, Van Zile said that other mainline churches have toned down the anti-Israel rhetoric in recent years. Sean Savage, Jewish Journal, "Presbyterian Church continues trend of targeting Israel at its General Assembly," 26 June 2018 Underground and mainline stations were evacuated as Metropolitan Police and firearms specialists responded, according to the British Transport Police. Casey Quackenbush, Time, "British Police Have Arrested a Man in Connection With London Railway 'Bomb Hoax'," 22 June 2018 According to PSA Airlines, an American Airlines regional carrier, the issue did not affect any of its other regional carriers or mainline flights. charlotteobserver, "'Irate passenger' strikes window at Charlotte airport after flight was canceled, CMPD says," 19 June 2018 Jones ran not just as a Democrat, but a mainline liberal Democrat and was able to win Alabama, a feat even given the unique weakness of his Republican opponent, Roy Moore. NBC News, "Democrat Doug Jones offers his party a recipe for success beyond Alabama," 15 May 2018

Recent Examples on the Web: Noun

By 1929, Daley and the now-18 operators who reported to her were working out of more established quarters on the fifth floor of the Cannon Office Building, handling around 30,000 calls a day over 100 main lines and 1,000 stations. New York Times, "Overlooked No More: Harriott Daley, the Capitol’s First Telephone Operator," 23 Apr. 2018 When the Long Island Rail Road began to extend its main line between Hicksville and Cold Spring Harbor in 1854, East Woods lay along the route. Julie Lasky, New York Times, "Syosset, N.Y.: Suburban Subdivisions and Wooded Hillsides," 11 Apr. 2018 Fredyson Martinez, vice president of a union that represents power company workers, said in a phone interview that another line the company was trying to use to help back up the main line also failed on Thursday for unknown reasons. CBS News, "Power outage in Puerto Rico leaves hundreds of thousands without electricity," 12 Apr. 2018 Instead of getting Jesus on the main line, Briese decided to call his Lord and Savior from whom all white things flow: the police. Michael Harriot, The Root, "#MourningWhileBlack: Priest Calls Cops on Black Funeral-Goers, Tells Them to 'Get the Hell Out' of Church," 2 July 2018 In May 27, a spill was reported from the main line north of Kamloops. Hal Bernton, The Seattle Times, "Canada acquires key pipeline link to Washington refineries," 11 June 2018 Rihanna has made statements about her main line, designing for women of all shapes and sizes. Avery Matera, Teen Vogue, "Rihanna’s Savage X Fenty Lingerie Has Completely Sold Out," 8 June 2018 Some of the items in the collection are actually re-branded best sellers from Inglot’s main line, and this eyeliner is one of them. Ashley Weatherford, The Cut, "Jennifer Lopez Knows How to Make a Great Mascara," 26 Apr. 2018 The Exchange Slav which people tell me is not without a touch of poison for Black 4.Bf4 Nf6 5.Nc3 Nc6 6.Nf3 a6 7.Rc1 Bf5 8.e3 Rc8 9.Be2 e6 10.0–0 Nd7 10...Bd6 is the main line here. Chris Chase, BostonGlobe.com, "Chess notes," 10 June 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'mainline.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of mainline

Verb

1938, in the meaning defined at transitive sense

Adjective

1941, in the meaning defined above

Noun

1841, in the meaning defined at sense 1

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Dictionary Entries near mainline

Mainite

mainland

Mainland

mainline

main line

mainliner

mainly

Statistics for mainline

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Time Traveler for mainline

The first known use of mainline was in 1841

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More Definitions for mainline

mainline

verb

English Language Learners Definition of mainline

 (Entry 1 of 3)

: to inject (a drug) directly into a vein

mainline

adjective

English Language Learners Definition of mainline (Entry 2 of 3)

: belonging to an established and widely accepted group or system

main line

noun

English Language Learners Definition of main line (Entry 3 of 3)

: an important highway or railroad line

mainline

verb
main·line | \ ˈmān-ˈlīn \
mainlined; mainlining

Medical Definition of mainline 

(Entry 1 of 2)

transitive verb

slang : to take by or as if by injecting into a principal vein

intransitive verb

slang : to mainline a narcotic drug (as heroin)

main line

noun

Medical Definition of main line (Entry 2 of 2)

slang

: a principal vein of the circulatory system

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