\ 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

That shooting followed back-to-back-to-back massacres in Gilroy, Calif., El Paso, Texas, and Dayton, Ohio. Christal Hayes, USA TODAY, "Thrust into gun debate, Scalise says being a shooting survivor doesn't mean it's his No. 1 priority," 16 Sep. 2019 In violent back-to-back incidents Saturday night in Mill Valley, an 18-year-old allegedly punched his Uber driver in the face and minutes later stabbed a 15-year-old boy at the same intersection. Anna Bauman,, "Police: Mill Valley teen turns himself in after punching Uber driver, stabbing boy," 16 Sep. 2019 The back-to-smoke trend flies in the face of the e-cig industry’s most insistent PR pitch: Vaping helps people quit smoking cigarettes. Los Angeles Times, "Vapers seek relief from nicotine addiction by turning to cigarettes," 16 Sep. 2019 His power numbers really picked up in his third season, and Banks’ back-to-back MVP seasons came in ’58 and ’59, his sixth and seventh seasons. Paul Sullivan,, "Kris Bryant set a Cubs record for home runs in his first 5 years. How does his output compare to Ernie Banks?," 16 Sep. 2019 Williams then struck quickly with back-to-back passes to Osborn of 21 and 22 yards, the second going for a touchdown to send Miami into the locker room up, 28-0. David Furones,, "Just what they needed: Miami Hurricanes win home opener convincingly over Bethune-Cookman," 15 Sep. 2019 Playing at home for the first time in three weeks, and coming off back-to-back setbacks on the road, SAFC wasted little time in grabbing control. Terrence Thomas,, "Castillo, SAFC rise to occasion for crucial win," 15 Sep. 2019 The Fighting Irish coach, about to go 9-1 in home openers with this 66-14 shellacking of a Mountain West foe coming off back-to-back 3-9 seasons, was absolutely livid. Mike Berardino, Indianapolis Star, "Brian Kelly: More explosive plays needed if Notre Dame is to stay with powerful Georgia," 14 Sep. 2019 After back-to-back games to start the season of overcoming fourth-quarter deficits, the coaching staff would appreciate a tranquil final stanza. Robert Avery, Houston Chronicle, "Deer Park hopes its fourth-quarter drama won’t be needed in Katy Saturday night," 14 Sep. 2019

Recent Examples on the Web: Adverb

Helmeted riot police lined the route and started seizing demonstrators from a scattered crowd on Pushkin Square and pushing them back from another square further along the route. Washington Post, "The Latest: Arrests at unsanctioned Moscow protest up to 600," 4 Aug. 2019 After a lengthy hiatus, the former teen heroes are back on the cartoon screen working day jobs, dating, living together and mourning their dead. Frederick Melo, Twin Cities, "Superheroes behaving badly: 12 crusading TV series target mature audiences," 4 Aug. 2019 After Boyd allowed runs in each of the third and fourth innings, Harold Castro put the Tigers (32-74) back on top with a two-run single up the middle in the fifth. Anthony Fenech, Detroit Free Press, "Detroit Tigers drop fly ball, later lose to Rangers on walk-off HR in 10th," 4 Aug. 2019 The earlier date for the poem helps push back the timeline for Medieval erotic poetry and suggests openness about sexuality appeared in the German speaking world earlier than previously thought. Jason Daley, Smithsonian, "Fragment of ‘The Rose Thorn,’ a Poem About a Talking Vulva, Dated to the 1300s," 3 Aug. 2019 At the park dedication Saturday, Cummings pushed back on Trump's criticism. Ledyard King, USA TODAY, "'Don't just come and criticize': Elijah Cummings defends Baltimore in face of Trump's insults," 3 Aug. 2019 The rapper landed back on U.S. soil Saturday, leaving behind him the looming verdict in an episode that has led to unexpected tension between the U.S. and its European ally. Linda Givetash, NBC News, "U.S. warned Sweden of 'negative consequences' if ASAP Rocky wasn't released," 3 Aug. 2019 As the player now actively pushes for an exit from the French champions, here's a look back at six defining moments of the Brazilian's spell at PSG., "Neymar: 6 Defining Moments of the Brazilian's Two Years at Paris Saint-Germain," 3 Aug. 2019 This should come as a thrill to those who wait all year for the seasonal latte to land back on Starbucks menus, which typically occurs near the end of August. Hannah Chubb,, "Starbucks Launches Pumpkin Spice Latte Coffee Creamer and You Can Get It Now," 2 Aug. 2019

Recent Examples on the Web: Adjective

Rather than sitting on traditional cushions, chairs were built into a platform to give him more back support. Washington Post, "Trump to Face Off With Japan’s Abe on Trade After Golf and Sumo," 18 Sep. 2019 The first is Apple’s challenge to the EU antitrust ruling that forced it to pay Ireland some $15 billion in back taxes. David Meyer, Fortune, "The Markets’ Fed Bet: CEO Daily," 17 Sep. 2019 Some of what Sullivan initially learned about transgender culture came from an underground network of confidantes who found each other via the back pages of community newsletters and magazines. Jeremy Lybarger, The New Yorker, "Lou Sullivan’s Diaries Are a Radical Testament to Trans Happiness," 16 Sep. 2019 Punch a hole in each corner of the base rectangle, then pull the elastic string through to create a front and back loop, and knot tightly. Jessy Ellenberger, Woman's Day, "Jaws with Claws Costume," 9 Sep. 2019 Nah’Shon Godfrey hauled in an interception along the back line of the end zone, which all but ended things Saturday afternoon at Kenneth R. Gill Stadium. Pat Stoetzer,, "College Football: McDaniel enjoys ‘a great day,’ first home win since 2017," 7 Sep. 2019 Such is the symbiotic relationship of the front and back ends of a defense. Los Angeles Times, "NFC West preview: 49ers hope bolstered pass rush will help them take division title," 2 Sep. 2019 Left tackle Taylor Decker, who was questionable with a back injury during practice, was inactive. Carlos Monarrez, Detroit Free Press, "Halftime observations: Detroit Lions bitten by special teams again, trail 10-6," 15 Sep. 2019 The former had earned his first ever senior call-up, but a back injury forced his early return to Manchester, while the latter has been suffering from a bout of illness., "Solskjaer: Pogba, Martial Out for Man United vs. Leicester Amid Growing Injury Crisis," 13 Sep. 2019

Recent Examples on the Web: Verb

Rodgers wasn't alone in praising Maguire either, as former teammate Jonny Evans has backed the England international to eventually become Manchester United captain during a potential 10-year spell in the north-west., "Brendan Rodgers & Jonny Evans Wax Lyrical About Harry Maguire Ahead of Reunion at Old Trafford," 14 Sep. 2019 Fajgenbaum hopes his story offers lessons, far beyond medicine, about what people can do when they're backed against a wall. Ryan Prior, CNN, "This med student was given last rites before finding a treatment that saved his life. His method could help millions," 14 Sep. 2019 Their differences involve key policy issues — Warren backs Medicare for All while Biden supports expanding on Obamacare — and campaign decisions, Warren rejects fundraisers while Biden is courting big donors. Sarah Ewall-wice, CBS News, "The frontrunner meets the rising star: Biden and Warren take center stage at third debate," 11 Sep. 2019 Frank Sinatra did it for both parties, backing John F. Kennedy and later Ronald Reagan. New York Times, "What Can a Star Like Cardi B Do for a Politician Like Sanders?," 11 Sep. 2019 Learn how food waste can be transformed into fuel and fertilizer, and then back into food during a workshop. National Geographic, "Engineering and Robotics on the MIT Campus," 10 Sep. 2019 After rushing for more than 230 yards in a season-opening win over Wagner, UConn couldn’t get much going on the ground Saturday, as running backs Kevin Mensah and Art Thompkins generated only 41 yards between them. Alex Putterman,, "UConn football keeps game close behind freshman quarterback, falls just short in 31-23 loss to Illinois," 8 Sep. 2019 There’s also the question of whether Sanders would back the elimination of the filibuster, as Warren has done, to pass climate legislation. Mark K. Matthews, Scientific American, "Five Things to Watch During CNN’s Climate Forum," 4 Sep. 2019 The Kremlin blocked her visit after Congress passed a tough Russia sanctions bill that Shaheen had vocally backed. Deirdre Shesgreen, USA TODAY, "Russia bars Sens. Ron Johnson and Chris Murphy from Moscow visit in 'petty affront'," 21 Aug. 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

1 Oct 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).


a bell tower

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