\ˈmān \

Definition of main 

(Entry 1 of 3)

1 : physical strength : force used in the phrase with might and main

2a : mainland

b : high sea

3 : the chief part : essential point they are in the main well-trained

4 : a pipe, duct, or circuit which carries the combined flow of tributary branches of a utility system

5a : mainmast

b : mainsail



Definition of main (Entry 2 of 3)

1 : chief, principal the main idea

2 : fully exerted : sheer main force by main strength

3 obsolete : of or relating to a broad expanse (as of sea)

4 : connected with or located near the mainmast or mainsail

5 : expressing the chief predication in a complex sentence the main clause


geographical name
\ˈmīn, ˈmān\

Definition of Main (Entry 3 of 3)

river 325 miles (523 kilometers) long in south central Germany rising in northern Bavaria in the Fichtelgebirge and flowing west into the Rhine River

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Examples of main in a Sentence


My radio runs either off batteries or off the mains. Turn off the water at the mains.


Speed is the main advantage of this approach. The company's main office is located in New York. driving down the main road This dish can be served as a main course or appetizer. And now for the main event of the evening!
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Recent Examples on the Web: Noun

Here, Dior shared a few behind-the-scenes photos of the making of the dress exclusively with Vogue, plus a video of the petites mains at work in the atelier. Emily Farra, Vogue, "When Beige Isn’t Boring: The Story Behind Dior’s Toile de Jouy Couture Gown," 6 July 2018 The menu’s other two mains, skirt steak and wild coho, are grilled over oak with the same exactitude. Providence Cicero, The Seattle Times, "Central Smoke’s Asian-accented, down-home barbecue adds fire and spice to chilly nights," 25 Oct. 2018 An explosion rocked the city of Sun Prairie, Wis., on Tuesday after a contractor struck a natural gas main, leveling buildings and injuring at least two firefighters and one police officer, authorities said. Nicole Darrah, Fox News, "Wisconsin gas explosion levels Main Street buildings; firefighters, police officer reported injured," 2 Oct. 2018 Amy Jahns is a spokeswoman for We Energies, which owns the gas main. Todd Richmond,, "Communications subcontractor 'on site' ahead of fatal Wisconsin blast that killed firefighter, injured 11," 12 July 2018 Schulze said a 4-inch gas main was struck by a contractor, which caused the gas leak. Meg Jones, Milwaukee Journal Sentinel, "Sun Prairie firefighter killed by explosion that destroyed his own bar," 11 July 2018 Most Roma do not have access to mains water, the report said. Washington Post, "Survey shows unemployment, poverty among W. Balkans’ Roma," 9 May 2018 WE Energies spokeswoman Amy Jahns said workers for a private contractor punctured a 4-inch gas main, causing a leak that resulted in the explosion. Christopher Brito, CBS News, "J.J. Watt quietly donates $10K to fallen Wisconsin firefighter's family," 12 July 2018 WE Energies spokeswoman Amy Jahns said workers for a contractor apparently punctured a 4-inch natural gas main, sending gas leaking into a building ahead of the explosion. NBC News, "Sun Prairie, Wisconsin explosion: Firefighter dies after natural gas main erupts," 11 July 2018

Recent Examples on the Web: Adjective

Coal hasn't necessarily suffered because of a lack of growth, although that is a main reason why coal is struggling to make a comeback under a favorable administration. Megan Geuss, Ars Technica, "As US coal use drops to 1979 levels, EPA may ease rules on new coal plants," 5 Dec. 2018 Tesla representatives praised the relationship with Panasonic and cited the tight integration with the battery maker as a main reason why the company has a lead in cell cost. Sean O'kane, The Verge, "Tesla will live and die by the Gigafactory," 30 Nov. 2018 Jenny's main goal was to create a space that was beautiful but also approachable. Danielle Tullo, House Beautiful, "How Jenny Cipoletti Of Margo & Me Turned Her Apartment Into A Parisian Escape," 20 Nov. 2018 That's actually one of the main goals of this book. Lucia Tonelli, ELLE Decor, "Joanna Gaines’ New Book 'Homebody' Reminds Us Why There’s No Place Like Home," 8 Nov. 2018 The material temporarily loses some of its stickiness when kept in the cold for two main reasons: First, the cooler air cuts back on that annoying static electricity. Caroline Picard, Good Housekeeping, "Storing Plastic Wrap in the Freezer Makes It WAY Easier to Handle," 31 Oct. 2018 That's because they're typically saved for the big main event, such as weddings. Amanda Mitchell, Marie Claire, "Kate Middleton Really, Really Loves Princess Diana's Tiara," 23 Oct. 2018 One of the main reasons both Democrats and Republicans have embraced the measure is its promise of increased cost savings. Patrick Sisson, Curbed, "Climate change and the coming coastal real estate crash," 16 Oct. 2018 Busy, untraditional schedules and the desire for more variety throughout the day are some of the main reasons Americans are shifting away from a classic meal structure. Zoya Gervis, Fox News, "Majority of Americans no longer eat 3 meals a day, study finds," 27 Sep. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'main.' 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 main


before the 12th century, in the meaning defined at sense 1


15th century, in the meaning defined at sense 1

History and Etymology for main


in sense 1, from Middle English, from Old English mǣgen; akin to Old High German magan strength, Old English magan to be able; in other senses, from main entry 2 or by shortening — more at may


Middle English, from Old English mǣgen-, from mǣgen strength

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Statistics for main

Last Updated

14 Dec 2018

Look-up Popularity

Time Traveler for main

The first known use of main was before the 12th century

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More Definitions for main



English Language Learners Definition of main

 (Entry 1 of 2)

: the largest pipe in a system of connected pipes

the mains : the system of pipes or wires for electricity, gas, or water

: the place where electricity, gas, or water enters a building or room



English Language Learners Definition of main (Entry 2 of 2)

: most important


\ˈmān \

Kids Definition of main

 (Entry 1 of 2)

: first in size, rank, or importance : chief Go in the main entrance. What's the main reason?

Other Words from main

mainly adverb



Kids Definition of main (Entry 2 of 2)

1 : the chief part : essential point The new workers are in the main well trained.

2 : a principal line, tube, or pipe of a utility system water main gas main

3 : high seas

4 : physical strength : force So they stood … both shoving with might and main— Mark Twain, Tom Sawyer

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More from Merriam-Webster on main

Rhyming Dictionary: Words that rhyme with main

Thesaurus: All synonyms and antonyms for main

Spanish Central: Translation of main

Nglish: Translation of main for Spanish Speakers

Britannica English: Translation of main for Arabic Speakers

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