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

bottleneck, jam, jam-up, logjam, snarl, tailback [British], tie-up

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Examples of backup in a Sentence


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

His pro career numbers are meager: 4-of-8 passing for 28 yards in four games as a backup for the New York Giants. Tyler Dragon,, "Reflecting back on Jared Lorenzen's NFL career with the New York Giants," 9 July 2019 Steph Curry scored 47 points to go with eight rebounds and seven assists, but couldn't do it all for the two-time defending champions, who were without starters Kevin Durant and Klay Thompson and key backup big man Kevon Looney because of injuries. Houston Mitchell,, "The Sports Report: Women's World Cup TV schedule," 6 June 2019 Unlike portable generators, they're installed permanently on a concrete pad in your yard and will provide uninterrupted backup for days. David Agrell, Popular Mechanics, "Should You Buy a Standby Generator?," 11 Sep. 2018 More: Who is left for the Pacers in free agency O'Quinn is a useful backup big man who averaged 7.1 points, 6.1 rebounds and 1.3 blocks for the Knicks last season. Matthew Glenesk, Indianapolis Star, "Pacers' free agency continues with big man Kyle O'Quinn," 6 July 2018 Then Uruguay after La Celeste presumably will have clinched passage to the second round and likely will send out the backups for a 90-minute kickaround. Mark Zeigler,, "Your guide to the World Cup you forgot was happening," 13 June 2018 Before their set, the Inciters will serve as backup for vintage soul-pop songstress Jackie Mendez (playing third), with reggae acts Scratch Outs and Triple Tree getting things started. Aaron Davis, sacbee, "LA rocker Kaz Mirblouk heads up list of upcoming must-see shows," 8 June 2018 With Thomas Davis suspended for the Panthers’ first four games for a PED violation, linebacker David Mayo will likely shift from a special teams role to a direct backup for Luke Kuechly and Thompson. Chapel Fowler, charlotteobserver, "Charlotte already offering opportunities for Panthers draft pick Jermaine Carter Jr. | Charlotte Observer," 23 May 2018 The three centers — in Doral; Hamburg, Germany, and Seattle — routinely scan for different ships but can act as backups for the entire fleet. Jane Wooldridge, miamiherald, "How does Carnival track its cruise ships? New high-tech center relies on big data. | Miami Herald," 11 May 2018

Recent Examples on the Web: Verb

The leggings will be anywhere from $39 to $46 during the sale, but will pop back up to between $59 and $69 on August 5, once the event wraps up. Alexis Rhiannon, Allure, "These Leggings Are Sure to Sell Out During the Nordstrom Anniversary Sale," 12 July 2019 The brick and glass high-rise will have views of downtown and backs up to Stemmons Freeway. Steve Brown, Dallas News, "Hillwood, USAA team up on Victory Park office tower," 8 July 2019 The two teams had only two days to rest, review film and travel back up the coast for round two of the series. Julia Poe, Pro Soccer USA, "Orlando City confident it can avenge loss during road rematch with Philadelphia Union," 6 July 2019 Before Hopper, Joyce, Murray, and Alexei (let’s call them Team Cherry) begin their mission, Hopper makes a quick, casual call to the military requesting back up that Joyce then makes again in order to convey the urgency. Kathryn Lindsay,, "R29 Binge Club: Stranger Things Season 3," 5 July 2019 Her glasses are another, pushed back up the bridge of her nose as a kind of nerd punctuation, a visual stammer. James Parker, The Atlantic, "Hannah Gadsby’s Genius Follow-Up to Nanette," 25 June 2019 Push into heels to rise back up to standing as you press kettlebell overhead (B). Rozalynn S. Frazier,, "Hit All Your Major Muscles With This 6-Move Kettlebell Workout," 10 June 2019 Holbrooke and Clark are told that a vehicle has gone off the side of the mountain back up the road. Thomas Powers, The New York Review of Books, "The Fog of Ambition," 6 June 2019 There are probably times those feelings bubble back up to the surface. Nick Talbot,, "Making DeRozan ‘sacrificial lamb’ was Raptors’ only choice," 5 June 2019

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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Statistics for backup

Last Updated

21 Jul 2019

Look-up Popularity

Time Traveler for backup

The first known use of backup was in 1801

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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



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

Rhyming Dictionary: Words that rhyme with backup

Thesaurus: All synonyms and antonyms for backup

Spanish Central: Translation of backup

Nglish: Translation of backup for Spanish Speakers

Britannica English: Translation of backup for Arabic Speakers

Comments on backup

What made you want to look up backup? Please tell us where you read or heard it (including the quote, if possible).


to complain fretfully

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