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 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Through the mid-20th century, most Protestants in the U.S. belonged to mainline churches, but now they are outnumbered by evangelicals. The Salt Lake Tribune, "The election spotlight mostly bypasses mainline Protestants," 14 Sep. 2020 Recent Examples on the Web: Adjective Loki seems not to be the Loki who got killed in the mainline continuity. Adam Rogers, Wired, "WandaVision Brought the Multiverse to Marvel," 11 Feb. 2021 Airlines such as Spirit and Allegiant have expanded rapidly to new destinations, hoping to grab market share from mainline competitors such as American Airlines and even Southwest. Dallas News, "Ultra-low-cost carrier Sun Country adds flights from DFW to California and Mexico for as low as $49," 25 Jan. 2021 Next up is work on the mainline Kennedy and Dan Ryan. Robert Channick, chicagotribune.com, "Final four ramps to open as Jane Byrne Interchange construction shifts to mainline Kennedy and Dan Ryan," 11 Dec. 2020 Just as striking, a number of mainline conservatives in the House are speaking openly about how much Mr. Trump damaged himself in the aftermath of the election, culminating with his role in inspiring the riots. New York Times, "Post Trump, Republicans Are Headed for a Bitter Internal Showdown," 16 Jan. 2021 For mainline Protestants like me, the discontent has been less visible. Fred Bahnson, Harpers Magazine, "The Gate of Heaven Is Everywhere," 5 Jan. 2021 Perhaps the strongest indication of the hegemony of mainline Protestantism during the early era of the court is how little it was questioned. Nomi Stolzenberg, The Conversation, "Religious identity and Supreme Court justices – a brief history," 19 Oct. 2020 Alaska Airlines has about 2,850 mainline jet pilots in total. Author: Dominic Gates, Anchorage Daily News, "Alaska Airlines orders more Boeing 737 MAXs to replace most of its Airbus jets," 22 Dec. 2020 While Catholic churches and nondenominational churches have reopened their doors with limited seating, most mainline Protestant churches are still closed. Jean Hopfensperger, Star Tribune, "COVID-19 sparks Christmas creativity in Minnesota," 19 Dec. 2020 Recent Examples on the Web: Noun The second, main line of storms moving through in the early evening and lasting into the early morning of New Year's Day. Mark Schleifstein, NOLA.com, "On New Year's Eve, hail, tornadoes possible in south Louisiana," 30 Dec. 2020 The weather service said a squall line of storms will be possible ahead of a cold front, and individual storms will also be possible ahead of the main line. Leigh Morgan, al, "Severe storms, tornadoes possible in Alabama on New Year’s Eve," 30 Dec. 2020 Simply attach the GoFish Cam to your main line and leader line to record or live-stream its footage on your phone and on social media. Popular Science, "We’ve rounded up 21 deals on stocking stuffers that won’t break the bank," 15 Dec. 2020 Some Texans, like Ozona resident Sean Sanchez, 52, have had luck in recent months calling TWC’s main line first thing in the morning. Sally Beauvais, ProPublica, "A Guide to Navigating the Texas Unemployment System During the Coronavirus Pandemic," 5 Dec. 2020 Farmers say agents are a vital cog of the farm economy and their main line of credit, providing quick funds for fuel, fertilizers, and even loans in case of family emergencies. Sheikh Saaliq, The Christian Science Monitor, "‘Our land is our mother’: Farmer protests fill New Delhi streets," 4 Dec. 2020 Both anglers should carefully grip the main line and pull their way along it, removing fish and rebaiting. Keith Sutton, Outdoor Life, "3 Ways to Catch Big Catfish Without a Rod and Reel," 24 Nov. 2020 The main line had 134 aircraft in its fleet at the end of December last year, including 19 A380s. Kyunghee Park, Bloomberg.com, "Singapore Air Reports Its Biggest-Ever Loss," 6 Nov. 2020 There are lures, particularly spinners and jigs, that require a short leader line to keep them from becoming tangled in the main line. Michael Pollick, chicagotribune.com, "The best fishing lure set," 17 Oct. 2020

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

Time Traveler

The first known use of mainline was in 1841

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Cite this Entry

“Mainline.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/mainline. Accessed 8 Mar. 2021.

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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

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