\ˈbak \
plural backs

Definition of back 

(Entry 1 of 5)

1a(1) : the rear part of the human body especially from the neck to the end of the spine

(2) : the body considered as the wearer of clothes They were left with nothing but the clothes on their backs.

(3) : capacity for labor, effort, or endurance Put your back into it!

(4) : the back considered as the seat of one's awareness of duty or failings get off my back

(5) : the back considered as an area of vulnerability the police officer's partner always watches his back

b : the part of a lower animal (such as a quadruped) corresponding to the human back riding on the back of an elephant

c : spinal column She had surgery on her back.

d : spine sense 1c The title is on the book's back.

2a : the side or surface opposite the front or face I only saw him from the back. : the rear part the back of the head the back of the mirror also : the farther or reverse side wrote the number on the back of an envelope

b : something at or on the back for support back of a chair

c : a place away from the front sat in back

3 : a position in some games (such as football or soccer) behind the front line of players also : a player in this position a defensive back

4 informal : a swimming race in which swimmers use the backstroke She placed first in the 100-meter back.

back of one's hand or back of the hand

: a show of contempt

back of one's mind

: the part of one's mind where thoughts and memories are stored to be drawn on

behind one's back

: without one's knowledge talking about me behind my back

in back of

: behind One day, I was sitting in the tiny parlor in back of the store …— John McNulty



Definition of back (Entry 2 of 5)

1a : to, toward, or at the rear asked the crowd to move back

b : in or into the past : backward in time looking back on her youth an event back in the last century Back then, no one had ever heard of chronic fatigue syndrome. also : ago several years back met him in the street two days back

c : to or at an angle off the vertical leaned back on his chair

d(1) : under restraint He wanted to fight but his friends held him back. holding back a laugh

(2) : in a delayed or retarded condition Bad weather set the launch date back several days.

e : in an inferior or secondary position especially : behind a competitor in points or ranking finished three strokes back

2a : to, toward, or in a place from which a person or thing came She left home and never went back. put the book back

b : to or toward a former state went back to private life

c : in return or reply forgot to write back



Definition of back (Entry 3 of 5)

1a : being at or in the back back door

b : distant from a central or main area back roads

c of a speech sound : articulated at or toward the back of the oral passage : formed deep within the mouth back vowels

2 : having returned or been returned

3 : being in arrears : overdue is owed several months in back pay

4 : moving or operating backward : reverse back action with oars

5 : not current back issues of a magazine

6 golf : constituting the final 9 holes of an 18-hole course


backed; backing; backs

Definition of back (Entry 4 of 5)

transitive verb

1a : to support by material or moral assistance backing a candidate for governor often used with up back up a friend in a fight

b : substantiate often used with up needs to back up her argument with evidence

c : to assume financial responsibility for back a new company

d : to provide musical accompaniment for often used with up a singer backed up by a guitarist

2a : to cause to go back (see back entry 2 sense 1a) or in reverse back the car into the garage

b : to articulate (a speech sound) with the tongue farther back : to form deeper within the mouth

3a : to furnish with a rear part : to furnish with a back (see back entry 1 sense 2) back a skirt with stiff material

b : to be at the rear part of : to be at the back (see back entry 1 sense 2) of a row of garages back the building

intransitive verb

1 : to move backward backed into a parking space often used with up back up to give him some spaceLet's back up a little to clarify what we're saying.

2 of the wind : to shift counterclockwise — compare veer entry 1 sense 2

3 : to have the rear part facing in the direction of something The house backs onto a golf course.

back and fill

1 nautical : to manage the sails of a ship so as to keep it clear of obstructions as it floats down with the current of a river or channel

2 : to take opposite positions alternately : shilly-shally has been back and filling on the issue

back into

: to get into inadvertently backed into the antiques business


geographical name
\ˈbak \

Definition of Back (Entry 5 of 5)

river 605 miles (974 kilometers) long in Nunavut, Canada, rising along the border with the Northwest Territories and flowing east-northeast into the Arctic Ocean

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Other Words from back


backed \ˈbakt \ adjective
backless \ˈbak-ləs \ adjective


backer \ˈba-kər \ noun

Synonyms & Antonyms for back

Synonyms: Noun

rear, reverse, tail

Synonyms: Adverb

backward (or backwards), rearward (also rearwards)

Synonyms: Adjective

aft, after, hind, hinder, hindmost, posterior, rear, rearward

Synonyms: Verb

abet, aid, assist, backstop, help, prop (up), support

Antonyms: Noun

face, forehead, forepart, front

Antonyms: Adverb

ahead, along, forth, forward, forwards, on, onward (also onwards)

Antonyms: Adjective

anterior, fore, forward, front, frontal

Antonyms: Verb


Visit the Thesaurus for More 

Choose the Right Synonym for back


support, uphold, advocate, back, champion mean to favor actively one that meets opposition. support is least explicit about the nature of the assistance given. supports waterfront development uphold implies extended support given to something attacked. upheld the legitimacy of the military action advocate stresses urging or pleading. advocated prison reform back suggests supporting by lending assistance to one failing or falling. refusing to back the call for sanctions champion suggests publicly defending one unjustly attacked or too weak to advocate his or her own cause. championed the rights of children

recede, retreat, retract, back mean to move backward. recede implies a gradual withdrawing from a forward or high fixed point in time or space. the flood waters gradually receded retreat implies withdrawal from a point or position reached. retreating soldiers retract implies drawing back from an extended position. a cat retracting its claws back is used with up, down, out, or off to refer to any retrograde motion. backed off on the throttle

Examples of back in a Sentence


She was carrying her little daughter on her back. She has a pain in the small of her back. I slapped him on his back to congratulate him. She stabbed him in the back. He was handcuffed with his hands behind his back. a bird with a spotted back riding on the back of a horse a comfortable chair with a padded back


The soldiers moved back from the front lines. The police asked the crowd to move back from the scene of the accident. He left his friends two miles back. She turned around and looked back toward him. a chapter beginning several pages back He left his home and never went back. It's time to go back home. She took the book off the shelf and forgot to put it back. In the opening chapter the author looks back on his youth. an event back in the last century


He keeps his wallet in his back pocket. We came in through the back entrance. We drove on the back roads instead of the main roads. The company owes him several months in back pay.


I'm backing him for President. She backed the winner of the race and won a lot of money. She backed her argument with written evidence. She backed the singer on the guitar. She backed into a parking space. She backed out of the garage. The dog kept growling but backed off cautiously. back a skirt with stiff material
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Recent Examples on the Web: Noun

Wheatcroft, who led on Thursday after the best round of his career, made three bogeys on his back nine., "Robert Rock takes two-shot lead at Scottish Open," 14 July 2018 Who wants a back-up who still views himself as an MVP candidate? Ben Golliver,, "Grades: Isaiah Thomas Can Rejuvenate Career in Nuggets' Low-Risk Gamble," 13 July 2018 Krasowski again commanded the back row for Sandburg in 2017, adding 410 digs. Tony Baranek, Daily Southtown, "The blue-and-gold standard: Volleyball standout Rachel Krasowski looking for junior achievement at Sandburg," 12 July 2018 There are no scenes of Mideast war slipped in here to give him a visible back story. Colin Covert, Detroit Free Press, "‘Leave No Trace’ is a moving father-daughter story," 12 July 2018 When the back-up unit arrived, the man jumped into the creek and disappeared, police said. Robert Moran,, "Man flees police traffic stop, dies in Wissahickon Creek," 11 July 2018 But that doesn’t seem like a reason for back-channel machinations that are likely to have adverse overall effects on infant health. Chloe Schama, Vogue, "Donald Trump Tweets About Breastfeeding—But Misses the Whole Point," 10 July 2018 Zsa Zsa’s family held a farewell ceremony for her in their back yard. Alix Langone, Time, "Zsa Zsa, The World's Ugliest Dog, Has Died Just 9 Days After Securing Her Title," 10 July 2018 From the back, the J. Mendel style featured cape-like sleeves that draped from her shoulders. Halie Lesavage, Glamour, "Melania Trump Wears Yellow J.Mendel Gown to State Dinner in England," 13 July 2018

Recent Examples on the Web: Adverb

The time has come for the Heat to determine whether Waiters is the closer going forward, or whether there will be a need to continue to bring back the likes of Wade or make plays for the likes of Anthony. Ira Winderman,, "With Ellington back, how do Heat manage glut at shooting guard?," 13 July 2018 World Team Tennis brings Spears back to her former home for the second straight year. Glae Thien,, "Abigail Spears’ net worth is still on upswing in tennis," 13 July 2018 According to the brand’s representatives, the film was fueled by a desire to bring back tales of the past. Sarah Nechamkin, The Cut, "Watch Kenzo’s Dreamy Reimagining of an Ancient Japanese Folktale," 13 July 2018 And smugglers brought it back to the U.S. to be sold on black markets. Carolyn Todd, Allure, "The History and Evolution of Birth Control in America," 12 July 2018 Bringing this less-common carryall back into the public’s eye is a reminder that men have a plethora of bag options available to them. Max Berlinger,, "LeBron James carries a $41,000 bag. Here's your chance to get into the man-bag game with these picks," 12 July 2018 Cordell was later traded for reliever Anthony Swarzak in 2017, Brinson was part of the trade package that brought back Christian Yelich before the 2018 season and Ortiz is one of the organization's top pitching prospects. Jr Radcliffe, Milwaukee Journal Sentinel, "Former Brewers catcher Jonathan Lucroy fumbles ball in bizarre walk-off loss to Houston," 11 July 2018 Before heading off to the afterlife, the Plaids are brought back to perform their one big gig. Emily Sorensen, Pomerado News, "Welk Theatre's 'Forever Plaid' opens Saturday," 11 July 2018 The Rising goalie sold him on the franchise, as his opinion held much weight with their friendship dating back to their time with Orange County. Clevis Murray, azcentral, "Phoenix Rising's Chris Cortez enjoying big season, life in Arizona, 'Game of Thrones'," 13 July 2018

Recent Examples on the Web: Adjective

But Avenatti soon broke his promise that the firm would meet a May deadline to pay the Internal Revenue Service $440,291 in back taxes, penalties and interest. Michael Finnegan,, "Bankruptcy judge hits Michael Avenatti's firm with restraining order to freeze legal fees in 54 cases," 12 July 2018 One contractor, which the audit didn’t name, owed the city $80,000 in back taxes but was paid more than $428,000 last year. Katie Honan, WSJ, "NYC Comptroller Audit Faults City for Paying Contractors Who Owe Taxes," 11 July 2018 Avenatti’s former firm, Eagan Avenatti LLP, had agreed in January to pay about $2.4 million in back taxes and penalties as part of a resolution of a bankruptcy case involving the firm. Mike James, USA TODAY, "Stormy Daniels' lawyer says he might run for president," 4 July 2018 In 2014, even while Hart was working his scheme, the city took the Greene Street property to sheriff’s sale for back taxes. Craig R. Mccoy,, "A Philadelphia story: Falsely declared dead, home stolen and no one will help," 29 June 2018 Comcast has agreed to pay $155 million in back taxes to Oregon in order to settle a nine-year property tax dispute. Jon Brodkin, Ars Technica, "Comcast drops bid for “gigabit” tax cut that was created for Google Fiber," 5 June 2018 Cohen's taxi medallion holding companies owe New York more than $280,000 in unpaid taxes, an analysis of state records shows, with nearly two-thirds of the back taxes owed from April. Kara Scannell, CNN, "'Taxi King' gets better plea deal after raid on Trump's lawyer," 29 May 2018 Evgeny Freidman, a taxi operator who allegedly owed some $5 million in back taxes, entered into the surprise plea deal in Albany on Tuesday. Fortune, "Michael Cohen's Taxi Partner Enters Plea Deal, Suggesting Cooperation," 22 May 2018 Court records in the bankruptcy proceeding also show Avenatti had personally agreed to pay about $2.4 million in back taxes and penalties. Michael Balsamo,, "Judge orders law firm of Stormy Daniels' lawyer to pay $10M," 22 May 2018

Recent Examples on the Web: Verb

Liberal activist groups are urging their supporters to attend a town hall meeting with Schumer in Brooklyn on Monday night and press him to commit to squeeze red-state Democrats who might feel pressure to back Trump’s pick. Chris Stirewalt, Fox News, "The new trustbusters," 3 July 2018 In the UnitedStates, the Environmental Protection Agency (EPA) has been backing research into new ways of evaluating chemicals through programs such as its Toxicity Forecaster (ToxCast) effort. Vanessa Zainzinger, Science | AAAS, "New digital chemical screening tool could help eliminate animal testing," 11 July 2018 Take your pick: From a DIY detox box and ready-to-heat vegetable bowls to a Kate Upton–backed plan, the options are more appealing than ever. Zoe Ruffner, Vogue, "5 New Healthy Meal-Delivery Programs, Just In Time for Summer," 11 July 2018 Several people spoke at this week’s City Council meeting asking aldermen to back the measure, even though there is no specific proposal before the council right now. Steve Lord, Aurora Beacon-News, "Residents push for Aurora welcoming ordinance to protect immigrants and refugees," 27 June 2018 The Habsburgs of Austria and the Bourbons of French sparred over control of the Spanish monarchy, and in their support of the Habsburgs, Catalonia ended up backing the wrong horse. Kate Keller, Smithsonian, "Beyond the Headlines, Catalan Culture Has a Long History of Vibrancy and Staying Power," 25 June 2018 Almost every single rumored 2020 candidate in the Senate has backed Sen. Bernie Sanders’a Medicare-for-all bill. Dylan Scott, Vox, "The “pleasant ambiguity” of Medicare-for-all in 2018, explained," 2 July 2018 Several Democratic senators, including Heidi Heitkamp (N.D.), Joe Manchin (W.Va.), and Joe Donnelly (Ind.) also backed Gorsuch and are facing reelection in states that Trump won. Natasha Bach, Fortune, "How an Alaska Senator Could Make or Break Trump's Supreme Court Plans," 2 July 2018 Costello also backs expansion of health savings accounts and wants Medicare Savings Accounts currently available elsewhere in the country to be made available to seniors in Florida. Steven Lemongello,, "Congress District 6: Where 6 candidates stand on issues," 13 July 2018

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


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


13th century, in the meaning defined at sense 1a


15th century, in the meaning defined at sense 1a


1548, in the meaning defined at transitive sense 1a

History and Etymology for back


Middle English, from Old English bæc; akin to Old High German bah back, Old Norse bak


Middle English bac, aphetic form of abak aback


Middle English, partly attributive use of bac, back back entry 1, partly derivative of back back entry 2


verbal derivative of back entry 1

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Dictionary Entries near back







backache brake

Statistics for back

Last Updated

15 Oct 2018

Look-up Popularity

Time Traveler for back

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

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More Definitions for back



English Language Learners Definition of back

 (Entry 1 of 4)

: the rear part of the body : the part of the body that is opposite to the stomach and chest and that goes from the neck to the top of the legs

: the part of an animal that is like a person's back

: the side or surface of something that is opposite the front or face : the rear side or surface of something



English Language Learners Definition of back (Entry 2 of 4)

: in, toward, or at the back or rear

: to, toward, or in the place where someone or something was previously

: in or into the past : backward in time



English Language Learners Definition of back (Entry 3 of 4)

: of or relating to the back : located at the back

: far from a central or main area

: not yet paid : owed from an earlier time



English Language Learners Definition of back (Entry 4 of 4)

: to give help to (someone)

: to bet on (someone or something)

: to provide evidence that supports (something)


\ˈbak \

Kids Definition of back

 (Entry 1 of 4)

1 : the rear part of the human body from the neck to the end of the spine : the upper part of the body of an animal

2 : the part of something that is opposite or away from the front part

3 : a player in a team game who plays behind the forward line of players

Other Words from back

backed \ˈbakt \ adjective a high-backed chair



Kids Definition of back (Entry 2 of 4)

1 : to, toward, or at the rear The crowd moved back.

2 : in or to a former time, state, or place I started working here some years back. I'll be right back.

3 : under control I kept back my anger.

4 : in return or reply Please write back. Give me back my bike.

back and forth

1 : toward the back and then toward the front

2 : between two places or people They sailed back and forth across the lake.



Kids Definition of back (Entry 3 of 4)

1 : located at the back the back door

2 : far from a central or main area back roads

3 : not yet paid : overdue He owes back rent.

4 : no longer published back issues of a magazine


backed; backing

Kids Definition of back (Entry 4 of 4)

1 : to give support or help to : uphold Which candidate are you backing?

2 : to move back She backed out of the garage.

back down

: to stop arguing or fighting for something You just can't back down and let people say I told you so.— Oliver Butterworth, The Enormous Egg

back off

: to back down

back out

: to decide not to do something after agreeing to do it

Other Words from back

backer noun


\ˈbak \

Medical Definition of back 

1a : the rear part of the human body especially from the neck to the end of the spine

b : the corresponding part of a lower animal (as a quadruped)

c : spinal column

2 : the part of the upper surface of the tongue behind the front and lying opposite the soft palate when the tongue is at rest

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Legal Definition of back 

1 : being overdue or in arrears back rent

2 : being retroactive especially as compensation reinstated with back pay

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Comments on back

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


evasion of direct action or statement

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