mainline

verb
main·​line | \ ˈmān-ˌlīn How to pronounce mainline (audio) \
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

But in 2003, James and his bandmates already seemed to be mainlining the same influences as the jam bands on Bonnaroo’s neighboring stages, channeling elements of the Dead, the Band, the Allman Brothers, maybe even a squirt of Parliament-Funkadelic. Chris Richards, Washington Post, "After a long, strange trip ... all your indie faves are jam bands now," 6 June 2019 In a city that mainlines major brands, d3 is a welcome change. Laura Ratliff, Condé Nast Traveler, "10 Best Shops in Dubai," 5 Mar. 2018 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

Recent Examples on the Web: Adjective

Cuomo announced a plan to restore voting rights to 35,000 parolees and helped broker a truce in a years-long standoff between rogue and mainline Democrats in the state Senate. Ella Nilsen, Vox, "Andrew Cuomo claimed America “was never that great”," 16 Aug. 2018 The United Methodist Church isn’t the first mainline Protestant denomination to reach a breaking point over LGBT rights. Ian Lovett, WSJ, "Methodist Church Faces Possible Schism Over Gay Rights," 21 Feb. 2019 In the Catholic Church and some mainline Protestant denominations, All Saints Day is still observed as a religious holiday, with the month of November given over to prayers for the dead. Regina Hansen, WSJ, "The Multicultural Past of Our Commercial Halloween," 26 Oct. 2018 Far fewer Catholics and white mainline Protestants considered this important. David Crary, The Seattle Times, "Poll: Voters open to candidates without deep religious faith," 11 Sep. 2018 But those looking for something a little more complex should look out for the Switch’s first mainline Pokémon adventure, which promises to be a more traditional role-playing game. Andrew Webster, The Verge, "The 40 games we can’t wait to play in 2019," 26 Dec. 2018 By comparison, United bumped 70 from mainline flights; American 1,041 and Southwest 2,012. Scott Mccartney, WSJ, "The Push to End Bumping Passengers From Flights," 5 Dec. 2018 The church is associated with the Disciples of Christ, a historically progressive-leaning mainline Protestant group. Tara Isabella Burton, Vox, "How faith leaders respond to tragedies like the California wildfires," 21 Nov. 2018 White mainline churches are emptying at an astonishing rate. Tara Isabella Burton, Vox, "White evangelicals are the only religious group to support Trump," 3 Oct. 2018

Recent Examples on the Web: Noun

Work on Prater Road is next, and the city will be updating the main line to the prisons and drainage work in Sunset Heights subdivision where there has been flooding for years. David Taylor, Houston Chronicle, "Dayton Mayor Wadzeck discusses future growth, road projects," 12 June 2019 Four thousand nine hundred eighty-nine and a half miles of gas-main lines of the state’s underground pipeline network belongs to a utility company called Columbia Gas of Massachusetts. Nathaniel Penn, Popular Mechanics, "The Day the Town Blew Up," 3 June 2019 Naturally, these mood-brightening and eclectic influences are reflected in both Kapadiya and Kumar’s personal wardrobes and their main line, too. Whitney Wei, Vogue, "Meet the Indian Design Duo Shaking Up the Look of Athleisure," 28 Nov. 2018 Wu is evolving his label and has recently rebranded his main line to Jason Wu Collection and his secondary line to Jason Wu. Brooke Bobb, Vogue, "Jason Wu Is Launching a Denim Collection With the Help of 3x1," 12 Sep. 2018 Investigators also are focusing on why a railroad switch was locked in the wrong position, sending the Amtrak train off the main line and onto the side track. Washington Post, "NTSB: Amtrak engineer sounded horn, applied emergency brake in S.C. crash," 5 Feb. 2018 Check the main line connection at the street and house. Gary Robbins, sandiegouniontribune.com, "Safety tips to follow before, during and after an earthquake," 8 July 2018 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

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

Last Updated

19 Jun 2019

Look-up Popularity

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)

slang : to inject (a drug) directly into a vein

mainline

adjective

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

chiefly US : 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 How to pronounce mainline (audio) \
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

More from Merriam-Webster on mainline

Rhyming Dictionary: Words that rhyme with mainline

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