number one


Definition of number one

 (Entry 1 of 2)

1 : one's own interests or welfare : oneself looking out for number one often written No. 1
2 : one that is first in rank, importance, or influence often written No. 1

number one


Definition of number one (Entry 2 of 2)

1 : first in rank, importance, or influence : foremost cancer is the country's number one killer often written No. 1
2 : of highest or of high quality

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Examples of number one in a Sentence

Noun Who's number one in this office? Getting the car fixed is number one on my list of priorities. I'll tell you why we can't go on a vacation: number one, we can't afford it, and number two, we'll miss my sister's party. Her movie is currently number one at the box office. When the goal was scored, the fans started to chant, “We're number one, we're number one.” I've been taking care of other people for too long. It's time for me to take care of number one. Adjective The book is the company's number one seller. Rule number one is don't get caught! He's public enemy number one: the nation's most wanted criminal.
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Recent Examples on the Web: Adjective For the 10th consecutive year, German Chancellor Angela Merkel took number one spot, while Christine Lagarde, president of the European Central Bank, came in second followed by U.S. Vice-President-elect Kamala Harris. NBC News, "Mika Brzezinski, Know Your Value and Forbes are gearing up to celebrate 50 trailblazing women over 50," 9 Dec. 2020 Companies must understand that the number one goal of health tech, unlike other tech, is not to engage and immerse patients in their phones but to support and embolden them in their real lives. Payal Marathe, STAT, "The mental health dilemma: If technology is the problem, can it also be the solution?," 8 Dec. 2020 In podcasting news, The Joe Rogan Experience took the number one spot for most popular podcast of the year globally, followed by TED Talks Daily, and The Michelle Obama Podcast. Andrea Romano, Travel + Leisure, "Here’s What People Listened to on Spotify During This Very Crazy Year," 1 Dec. 2020 In fact, Netflix shared that the series has hit the number one spot in 63 countries and launched the 37-year-old novel from which it's based onto The New York Times bestseller list. Emily Tannenbaum, Glamour, "The Queen's Gambit," 26 Nov. 2020 The Weeknd, who has three number one selling albums under his belt, will take over the field for halftime. Chris Morris, Fortune, "How to watch Super Bowl LV live online for free—without cable," 7 Feb. 2021 Seven said the number one barrier was the lack of rehearsal and performance space, with some noting that many cultural centers and performance spaces have simply not reopened. Michael Granberry, Dallas News, "‘It’s as bad as it sounds’: Pandemic cost Dallas arts $95 million in 2020," 5 Feb. 2021 The lush Lamb and Lion Inn in Barnstable is consistently ranked as a top pet-friendly inn; Yankee magazine named it the number one pet-friendly property in New England, and CNN called it one of the top 12 in the world. Pamela Wright,, "Pet-friendly places to stay in New England," 27 Jan. 2021 The Winx Saga, a fantasy YA drama that has been stuck in Netflix's number one slot since its January 22 debut. Andrea Park, Marie Claire, "'Fate: The Winx Saga' Season 2: Everything We Know So Far," 25 Jan. 2021

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


circa 1705, in the meaning defined at sense 1


1839, in the meaning defined at sense 1

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Time Traveler for number one

Time Traveler

The first known use of number one was circa 1705

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Statistics for number one

Cite this Entry

“Number one.” Dictionary, Merriam-Webster, Accessed 7 Mar. 2021.

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More Definitions for number one

number one


English Language Learners Definition of number one

 (Entry 1 of 2)

: a person, thing, or position that is highest in rank : the most important person or thing in a group of people or things
: the most successful person or thing in a group of people or things
: your own happiness, health, or success

number one


English Language Learners Definition of number one (Entry 2 of 2)

: highest in rank or importance

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