mainline

1 of 3

verb

main·​line ˈmān-ˌlīn How to pronounce mainline (audio)
mainlined; mainlining; mainlines

transitive verb

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

intransitive verb

slang : to mainline a narcotic drug

mainline

2 of 3

adjective

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

main line

3 of 3

noun

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
With a month or so in which to mainline asparagus, there’s no need to worry about tomatoes or zucchini. Yotam Ottolenghi, New York Times, 10 Apr. 2024 Even those who are not specifically mainlining these clips may suffer from an algorithmic selection bias: the more interest a person has in the recent plane malfunctions, the more likely that person might be to see more stories and commentary about planes in general. Charlie Warzel, The Atlantic, 20 Mar. 2024 Consider mainlining something that doesn’t feature on the diet plan. Raven Smith, Vogue, 10 Jan. 2024 Further out, there is a plan to move to mainline Linux. Ron Amadeo, Ars Technica, 20 Sep. 2023 Would Rory and Lorelai, devoted high-culture haters who prefer ordering pizza and mainlining Cop Rock to nosing around museums, ever be caught dead here? Emma Specter, Vogue, 28 Nov. 2023 To make crossing paths with Henry more bearable, Alex mainlines several expensive glasses of whiskey. Ct Jones, Rolling Stone, 11 Aug. 2023 Over the years, the gays and Jews (Ryan Murphy, Lena Dunham, Rachel Bloom, et al.) who grew up mainlining her show tunes have given her memorable cameos and supporting roles on shows such as Hollywood, Girls, and Will & Grace. Vulture, 13 June 2023 But simply mainlining Reddit's conversations for AI training purposes will come with a price, the exact amounts of which should arrive in the coming weeks. Kevin Purdy, Ars Technica, 19 Apr. 2023
Adjective
Only about half of its mainline jets come from Boeing, compared to about 80% of United Airlines’ fleet, and 100% of the planes flown by Southwest. Chris Isidore, CNN, 10 Apr. 2024 Monday’s development signals the fallout from Boeing’s production crisis is spilling over into airline operations, especially United, where 81% of its mainline operations use Boeing jets. Ramishah Maruf, CNN, 1 Apr. 2024 Evangelical protestants now make up a larger share of Greater Cincinnati’s population than Catholics and mainline protestants combined, according to the U.S. Religion Census. Dan Horn, The Enquirer, 20 Mar. 2024 The exodus marks a calamitous decline for the broader tradition of mainline Protestantism, which once dominated the American religious, social and cultural landscape. Ruth Graham, New York Times, 18 Dec. 2023 In-flight Wi-Fi United offers in-flight Wi-Fi for a fee on all its mainline aircraft and two-cabin regional planes. Eric Rosen, Travel + Leisure, 30 July 2023 Already, Taylor said, one of his new bosses had threatened to take his welding gang after Taylor shut down a mainline track. Danelle Morton, ProPublica, 18 Nov. 2023 For the first time in a mainline Street Fighter game, Capcom offers different control schemes that players can freely choose between. Aurich Lawson, Ars Technica, 30 May 2023 Indeed, whatever Trump's shortfalls, the challenge for DeSantis, Haley and the rest of his opponents is that winning the nomination necessarily means winning mainline Republicans and core GOP groups such as conservatives and evangelicals. Gary Langer, ABC News, 15 Jan. 2024
Noun
When this happens, your main line twists, and that twisting can travel far, even all the way to the reel spool. Joe Cermele, Outdoor Life, 7 Mar. 2024 Breeding salt-tolerant crops is another main line of research. The Arizona Republic, 15 Mar. 2024 Tie your main line to one eyelet, then add an 18- to 24-inch leader to the other eyelet, finishing with tying your spinner to the terminal end of the leader. Joe Cermele, Outdoor Life, 7 Mar. 2024 The answer to that question has already become one of Democrats' main lines of attack against Hovde. Journal Sentinel, 26 Feb. 2024 There have been two main lines of research into the problem: finding shapes that can’t be illuminated and proving that large classes of shapes can be. Quanta Magazine, 15 Feb. 2024 The tube is slid onto your main line first during rig construction. Joe Cermele, Field & Stream, 26 Oct. 2023 The wastewater is then returned through one main line back into the sewer system. Emilie Le Beau Lucchesi, Discover Magazine, 10 Apr. 2023 That gutting of the platform’s main line of defenses against violating content makes an already difficult content moderation challenge even more difficult, especially during viral moments where users flood the platform with more potentially violating content. Popular Science, 26 Jan. 2024

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'mainline.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

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

Time Traveler
The first known use of mainline was in 1841

Dictionary Entries Near mainline

Mainland

mainline

main line

Cite this Entry

“Mainline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mainline. Accessed 20 Apr. 2024.

Medical Definition

mainline

1 of 2 verb
main·​line ˈmān-ˈlīn How to pronounce mainline (audio)
mainlined; mainlining

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

2 of 2 noun
slang
: a principal vein of the circulatory system
Last Updated: - Updated example sentences
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