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

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 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

Recent Examples on the Web: Adjective

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 Anders was ordained in the United Church of Christ, a liberal mainline Protestant denomination, and preached for a time at Rockville United Church in Maryland. Hannah Natanson, The Seattle Times, "At the Church of the Wild, congregants wander silent and barefoot through nature," 6 Aug. 2018 This comes as the Presbyterians, like other mainline protestants churches, have faced rapidly declining memberships and an identity crisis that has allowed the more radical elements within the church to hijack the movement, observers say. Sean Savage, Jewish Journal, "Presbyterian Church continues trend of targeting Israel at its General Assembly," 26 June 2018

Recent Examples on the Web: Noun

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 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

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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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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