noun, often attributive
back·​up | \ ˈbak-ˌəp How to pronounce backup (audio) \

Definition of backup

 (Entry 1 of 2)

1a : one that serves as a substitute or support I brought an extra pencil for backup. a backup plan
b : musical accompaniment The tunes include banjo and guitar backup.
c : additional personnel who provide assistance The police officer called for backup.
2 : an accumulation caused by a stoppage in the flow traffic backup
3 : a copy of computer data (such as a file or the contents of a hard drive) I made a backup copy of the file. also : the act or an instance of making a backup

back up

backed up; backing up; backing up

Definition of back up (Entry 2 of 2)

intransitive verb

: to accumulate in a congested state traffic backed up for miles

transitive verb

1 : to move into a position behind (a teammate) in order to assist on a play
3 : to make a copy of (a computer file or data) to protect against accidental loss or corruption Be sure to back up your work. also : to make copies of all the files on (a device) a program that automatically backs up your hard drive

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Synonyms for backup

Synonyms: Noun

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Examples of backup in a Sentence

Noun His role on the team is to be a backup to the regular quarterback. We have an extra radio as a backup in case this one doesn't work. We have an extra radio for backup. He provides backup for the regular quarterback. She sang backup on his CD.
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Recent Examples on the Web: Noun After serving as Madubuike’s backup for years, this is the year for Peevy to make a name for himself in his senior season. Hannah Underwood, Dallas News, "Texas A&M roster rankings, Nos. 10-6: A trio of returning seniors highlights this group," 20 May 2020 Still, Sports Illustrated reported in its May 25 edition on the lingering problems and reminded readers that Atlanta had volunteered to be the emergency backup. Mark Schmetzer,, "Rockin' the Riverfront: It was a bumpy road en route to Riverfront Stadium construction," 16 May 2020 Jackson and Ware were recruited to play the four but at least one will likely need to play minutes at the five as Sarr’s backup under the current roster configuration. Jon Hale, The Courier-Journal, "No DeAndre Williams, so what are Kentucky basketball's options now in the frontcourt?," 15 May 2020 Stidham won the job as Brady’s backup from Brian Hoyer. Mark Inabinett |, al, "Kliff Kingsbury, Urban Meyer like Jarrett Stidham’s chances for success," 13 May 2020 Daniel is locked in as Stafford’s backup till 2022. Dave Birkett, Detroit Free Press, "If Detroit Lions pass on QB early in NFL draft, there's no reason to take one late," 17 Apr. 2020 The first hint of the growing backup had come two days before, when the funeral home had gotten a call about a man who'd died of coronavirus at home. Author: Stephanie Mccrummen, Anchorage Daily News, "Death without ritual," 5 Apr. 2020 By winning the Senate, Democrats could unclog the backup of crucial unpassed laws, decide the fate of the president’s agenda, and make sure far-right judges don't make it to the Supreme Court. Sophie Hayssen,, "Flipping The Senate Is Crucial This Fall. These 8 Women Can Make It Happen.," 3 Apr. 2020 Recent trade solicitations proved fruitless, and a day after sending Kyle Allen, Newton’s backup, to Washington and former Panthers coach Ron Rivera for a fifth-round pick, Carolina officially released Newton. Mike Jones, USA TODAY, "Opinion: Left in NFL limbo after his release by Panthers, Cam Newton must exhibit patience," 24 Mar. 2020 Recent Examples on the Web: Verb Traffic in the region’s biggest countries is back up to almost half of normal, according to the Inter-American Development Bank (IDB). The Economist, "Bello Latin America’s economic plight is getting worse," 23 May 2020 McConnell said the rule allowing a remote quorum raises constitutional questions, an opinion that is backed up by the Congressional Research Service. Susan Ferrechio, Washington Examiner, "'A flat-out lie': McConnell questions legality of House proxy-vote rule," 21 May 2020 After starting back up Sunday at Darlington Raceway, the NASCAR Cup series is also in the midst of its own stretch of five races in 15 days, with Darlington and Charlotte holding Sunday-Wednesday doubleheaders, followed by a race at Bristol May 31. Nathan Brown, The Indianapolis Star, "IndyCar schedule: Road America moves, adds doubleheader with loss of Richmond, Toronto," 21 May 2020 And across Alaska, restaurants, bars, and gyms, which have been open to small numbers of customers for weeks, were getting ready to rev back up to full capacity. Sarah Mervosh,, "All 50 States Are Now Reopening. But at What Cost?," 20 May 2020 The deputies called for back up, approached the camper and gave commands for Morse to come outside. John Sharp |, al, "Mobile County deputy shoots and kills man who pointed a gun at them," 20 May 2020 In their study of carbon dioxide emissions during the coronavirus pandemic, an international team of scientists calculated that pollution levels are heading back up — and for the year will end up between 4% and 7% lower than 2019 levels. Seth Borenstein, Anchorage Daily News, "Study: World carbon pollution falls 17% during pandemic peak," 20 May 2020 Indeed, in-store sales slowed during the first half of April but ramped back up mid-month as government stimulus money reached consumers, Walmart said. Phil Wahba, Fortune, "Walmart’s online sales surge during the pandemic, bolstering its place as a strong No. 2 to Amazon," 19 May 2020 The opinion from Judge Charles R. Simpson describes that in December 2006, Cosgrove shot 11 times at a car that backed up as the officer was trying to pull it over. Tessa Duvall, The Courier-Journal, "Who are the 3 Louisville officers involved in the Breonna Taylor shooting? What we know," 16 May 2020

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


1910, in the meaning defined at sense 1a


1801, in the meaning defined at intransitive sense

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Time Traveler for backup

Time Traveler

The first known use of backup was in 1801

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Statistics for backup

Last Updated

25 May 2020

Cite this Entry

“Backup.” Dictionary, Merriam-Webster, Accessed 30 May. 2020.

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More Definitions for backup

back up


Financial Definition of back up

What It Is

A back up is an increase in a security’s price, yield, or spread before issuance.

In other circles, back up means replacing a long-maturity security with a short-maturity security in order to capitalize on short-term interest rates that are higher than long-term interest rates.

How It Works

For example, let’s assume that Company XYZ wants to issue $100 million in 10-year bonds. The yields on bonds of similar quality and risk were about 5% when Company XYZ hired the underwriter to handle the bond issue, but since then the required yields have increased to 7%. This means Company XYZ has to issue the bonds at a bigger discount in order to keep the issue competitive, and thus it will obtain less cash from investors at the time of the sale.

This increase in the cost of issuing the securities is a back up.

Why It Matters

Back ups can be very detrimental to issuers, especially if they are relying on a very specific amount of money to come from the issue, and even more especially if the company’s success hinges on the reinvestment of those funds.

Source: Investing Answers


How to pronounce back up (audio)

English Language Learners Definition of backup

: a person or thing that can be used to replace or support another person or thing
: help or support provided by additional people or things
US : a situation in which the flow of something (such as traffic) becomes blocked


back·​up | \ ˈbak-ˌəp How to pronounce backup (audio) \

Kids Definition of backup

: a person who takes the place of or supports another The guard called for a backup.

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More from Merriam-Webster on backup

Thesaurus: All synonyms and antonyms for backup

Rhyming Dictionary: Words that rhyme with backup

Spanish Central: Translation of backup

Nglish: Translation of backup for Spanish Speakers

Britannica English: Translation of backup for Arabic Speakers

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