\ ˈbak How to pronounce back (audio) \
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 How to pronounce Back (audio) \

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 How to pronounce backed (audio) \ adjective
backless \ ˈbak-​ləs How to pronounce backless (audio) \ adjective


backer \ ˈba-​kər How to pronounce backer (audio) \ noun

Synonyms & Antonyms for back

Synonyms: Noun

rear, reverse, tail

Synonyms: Adverb

ago, agone [archaic], since, syne [chiefly Scottish]

Synonyms: Adjective

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

Synonyms: Verb

advocate, champion, endorse (also indorse), patronize, plump (for), plunk (for) or plonk (for) , support

Antonyms: Noun

face, forehead, forepart, front

Antonyms: Adverb


Antonyms: Adjective

anterior, fore, forward, front, frontal

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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

Her back wall often gets tagged with graffiti, but there’s been none since the bird appeared. Karina Bland, azcentral, "Is the crow on the bakery wall art or graffiti? The baker and the painter see art," 21 June 2019 Superstar or not, Armour played himself to the top on Thursday, shooting 6-under with four birdies on the back nine. Shawn Mcfarland,, "Ryan Armour, Abraham Ancer lead six-way tie at top of crowded leaderboard after Travelers Championship first round," 21 June 2019 Biscayne National Park is a national treasure in our back yard. Bonnie Gross,, "Boat tours explore underwater Biscayne National Park," 20 June 2019 The couple replaced a back wall with new glass doors and windows. J.s. Marcus, WSJ, "Old Intersects With New in This Former Dutch Church," 19 June 2019 The front door was open as the family’s large sheep dog barked from the back porch. Michael Todd, The Mercury News, "Aptos murder-suicide shocks hillside neighborhood," 19 June 2019 Jeans, and a Style Empire In the mid-1970s, when jeans were cut mostly for men, the clothing manufacturer Mohan Murjani signed Ms. Vanderbilt to market jeans for women with her signature on the back pocket. Robert D. Mcfadden, New York Times, "Gloria Vanderbilt Dies at 95; Built a Fashion Empire," 17 June 2019 Rose fell out of the race with three bogeys in a four-hole stretch on the back nine. Doug Ferguson, Houston Chronicle, "Gary Woodland claims U.S. Open title at Pebble Beach," 17 June 2019 Democrats, for the first two years of Trump’s presidency, got to sit in the back row and shoot spitballs. Alex Shephard, The New Republic, "House Leadership Is Looking Flakey," 17 June 2019

Recent Examples on the Web: Adverb

Some systems try to steer the vehicle back into its lane (assistance). Mark Phelan, Detroit Free Press, "These car features could prevent your next crash," 8 June 2019 Most exciting though is how the gameplay and liberal use of force abilities harken back to earlier third-person Star Wars games. Richard Newby, The Hollywood Reporter, "Is 'Fallen Order' the 'Star Wars' Game Fans Have Been Looking For?," 8 June 2019 Louisville is heading back to the College World Series for the fifth time in program history. Cameron Teague Robinson, The Courier-Journal, "Louisville baseball sweeps East Carolina, clinches fifth College World series berth," 8 June 2019 As the boat carried them on the final leg of their journey last month to the United States from Honduras, the young woman waved back to a group on Mexico’s riverbank cheering her rescue. New York Times, "Death on the Rio Grande: A Look at a Perilous Migrant Route," 8 June 2019 Then the party handed it out under its banner, with no trace back to the special interests that originally gave it. Willie Brown,, "Elizabeth Warren can win the nomination. California is key," 8 June 2019 The Museum of London, which chronicles the city as far back as 450,000 BC, when hippos filled what is now Trafalgar Square, has now come full circle by working to strike a deal to acquire Trump Baby. Richard Morgan, Fortune, "The Story Behind the Baby Trump Balloon," 8 June 2019 Junior defensive back Derrick Tucker was arrested Thursday after he was accused of misdemeanor assault during an incident in the early hours of March 24 in the Northgate bar district. Brent Zwerneman, Houston Chronicle, "Tacos tussle lands Texas A&M defensive back in jail," 8 June 2019 Pittman regained her footing in the next game, weathered volley after volley to climb back into the set. Tyler Kraft, Indianapolis Star, "Cathedral's Ellie Pittman, Carmel doubles duo win IHSAA individual tennis championships," 8 June 2019

Recent Examples on the Web: Adjective

Versatility between Justin Simmons, Kareem Jackson, Will Parks and Cravens gives Fangio any number of combinations on the back end. Kyle Fredrickson, The Denver Post, "Broncos safety Su’a Cravens found a mentor in Steve Atwater through difficult Denver debut," 8 June 2019 West Brom's quest to replace poor Darren Moore, who was booted out of the Hawthorns towards the back end of last season, has led them down many different paths - notably the ones owned by Slavisa Jokanovic and Slaven Bilic., "Derby New Kit, West Brom Prioritising Bilic & Birmingham Ground Share: Championship News Roundup," 7 June 2019 Photos show the side panel of the van close to the back end of the car, possibly lightly damaging the vehicles. Helen Murphy,, "Justin Bieber Gets Into Fender Bender in Los Angeles on the Way to Church with Hailey Baldwin," 6 June 2019 D’Hanis made it 3-0 in the fourth when Ethan Reyes drove in Jaeden VanDamme from second with a single and Luke Langfield stealing home on the back end of a double steal with Reyes going to second. David Hinojosa,, "D’Hanis shuts out New Home to claim 1A state title," 6 June 2019 Responding officers arrived at the home to find the boy had ran out the back door., "Family feuds at Elementary School property: South Euclid Police Blotter," 5 June 2019 After that, roles are up for grabs, particularly at the back end where no one had more than three saves. Jeff Metcalfe, azcentral, "ASU sticking with Tracy Smith as baseball coach after 15-win improvement over 2018," 4 June 2019 Seed Kitchen & Bar Seed Kitchen & Bar may be in the back corner of an East Cobb shopping center, but the interior feels like a Nordic living room. Jennifer Bradley Franklin, Condé Nast Traveler, "10 Best Brunch Places in Atlanta," 21 Aug. 2018 At the back corner of the Clover model, the floor raises into a platform hangout that looks remarkably like a conversation pit, only elevated. Liz Stinson, Curbed, "This tiny house comes with a conversation pit, sort of," 8 Aug. 2018

Recent Examples on the Web: Verb

Lawmakers in both parties backed the proposal, saying rural lawmakers especially are undercompensated for their costs of traveling to and staying in Phoenix during the session. USA TODAY, "Black Hills yaks, serious senioritis on campus, Pony Express: News from around our 50 states," 10 June 2019 The pope said in 2015 that the Catholic Church should view climate change as a moral issue, and has since used the Vatican’s diplomatic relations to back the Paris climate agreement and to push for stronger leadership in environmental protections. New York Times, "The Week in Business: YouTube Flip-Flops on Hate Speech," 8 June 2019 Instead, regional powers such as Egypt, the United Arab Emirates and Saudi Arabia, as well as France and Russia continue to back Hifter, while Turkey and other Western countries support the GNA. Sudarsan Raghavan, Washington Post, "In a city of ever-shifting front lines, Libyans confront their worst fighting in years," 4 June 2019 If the answer is no, then this is the team to back. Issie Lapowsky, WIRED, "How Early-Stage VCs Decide Where to Invest," 4 June 2019 The caucus, launched after a meeting convened by the American Jewish Committee in January, will work to bring blacks and Jews together to back hate crimes legislation and combat white supremacist ideology and actions. Ron Kampeas,, "Lawmakers launch congressional black-Jewish caucus," 4 June 2019 Mitch Thompson texted Butch on Monday morning, as the Tigers drove down I-85 from Atlanta to back home to a crowd of adoring fans outside of Plainsman Park. Sam Blum |,, "Auburn baseball stuck with Bailey Horn when it didn’t have to," 3 June 2019 In the trailer, Lisa is looking for someone to back her health start-up, and that's when Anne pops the question. Chloe Foussianes, Town & Country, "Renée Zellweger's Netflix Series What / If Is Out Now on Netflix," 24 May 2019 The rift on the issue has fallen along a rural-urban divide, with city dwellers more inclined to back the EU directive. Jamey Keaten, The Seattle Times, "Swiss voters approve tighter gun laws, lining up with the EU," 20 May 2019

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

25 Jun 2019

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 How to pronounce back (audio) \

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 How to pronounce back (audio) \

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)
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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More from Merriam-Webster on back

Rhyming Dictionary: Words that rhyme with back

Thesaurus: All synonyms and antonyms for back

Spanish Central: Translation of back

Nglish: Translation of back for Spanish Speakers

Britannica English: Translation of back for Arabic Speakers Encyclopedia article about back

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).


showing courage and determination

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