\ ˈbak How to pronounce back (audio) \
plural backs

Definition of back

 (Entry 1 of 4)

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 4)

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 4)

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 4)

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

Other Words from back


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


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

Synonyms & Antonyms for back

Synonyms: Noun

Synonyms: Adverb

Synonyms: Adjective

Synonyms: Verb

Antonyms: Noun

Antonyms: Adverb

Antonyms: Adjective

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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

Noun 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 Adverb 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 Adjective 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. Verb 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 See More
Recent Examples on the Web: Noun Back-to-back errors by Christian Arroyo at third base and Xander Bogaerts at shortstop led to two unearned runs in the third inning, erasing a lead the Sox had just grabbed with doubles by Bobby Dalbec and Duran. Julian Mcwilliams,, 1 Aug. 2022 Tens of thousands of students are missing from back-to-school rosters Los Angeles Unified Supt. Los Angeles Times, 1 Aug. 2022 The film follows Jack Nicholson’s Bobby Dupea, a former piano prodigy who has turned his back on his privileged lifestyle to embrace the life of a blue collar drifter. Brent Lang, Variety, 26 July 2022 True to his outsider leanings, the film tells the tale of a disconnected drifter, Bobby Dupea (Nicholson), who turns his back on his life of privilege and his talent as a piano prodigy to work on an oil rig. Chris Koseluk, The Hollywood Reporter, 24 July 2022 But will any of that matter if Tuesday’s numbers are so lackluster that Wall Street fully turns its back on Netflix? Nicole Goodkind, CNN, 17 July 2022 The report states Swavey, whose legal name was Earl Hatton, died from a gunshot wound to his back on Jan. 9, 2022. Nancy Dillon, Rolling Stone, 12 July 2022 Laying on his back on a couch, Ryan first expressed disbelief at what his sister told him. Andy Kostka, Baltimore Sun, 6 July 2022 Under the guidance of their leader, Astrid, the members within Falkreath Sanctuary have turned their back on Sithis, the Night Mother, and The Five Tenets. Wired, 5 July 2022 Recent Examples on the Web: Adverb Jonathan India looks back to full strength, hitting five home runs with an .892 OPS across 25 games in July. Jesse Yomtov, USA TODAY, 2 Aug. 2022 In Kabul and other cities, female activists have tried to fight back, holding numerous protests against new restrictions, but some rallies have been suppressed by police and none have made concrete gains. Pamela Constable, Washington Post, 2 Aug. 2022 That was the fastest rate of increase on record dating back to 2001. Rina Torchinsky, WSJ, 2 Aug. 2022 Housing inventory has surged in parts of the country as would-be home buyers, priced out by soaring inflation, have pulled back, analysts and real estate professionals say. Aaron Gregg And Yiwen Lu, Anchorage Daily News, 2 Aug. 2022 In Schultz’s back yard, the organizing quickly assumed a personal dimension. E. Tammy Kim, The New Yorker, 2 Aug. 2022 Taylor opted to push back the start of the offseason program two weeks and every practice was at a jog-through pace. Kelsey Conway, The Enquirer, 2 Aug. 2022 Translating his linebacker mentality back to offense provides another battering ram out in front of Henderson. Nathan Baird, cleveland, 2 Aug. 2022 The latest film in the Predator series turns the clock way back. Keith Phipps, Rolling Stone, 2 Aug. 2022 Recent Examples on the Web: Adjective According to a statement from the LAPD, Kupfer's attacker stabbed her with a knife before fleeing out the back door. Kc Baker,, 1 Aug. 2022 The waves at Aliomanu are gentle enough for year-round swimming, so enjoying the ocean is just a stroll away from the back door. Alexa Climaldi, Forbes, 31 July 2022 Extend your living space right off your back door with an attachable aluminum pergola kit from Purple Leaf. Samantha S. Thorpe, Better Homes & Gardens, 29 July 2022 His wife was babysitting and had the back door open two weeks ago when heavy rain fell and sent a few inches of rain and mud through the home. CBS News, 29 July 2022 The woman told deputies two men had come to the back door of the house while the victim was home alone, forced their way in and then beat her severely before leaving, the sheriff's office said. Fox News, 28 July 2022 Those interested in a meal should drive to the back door of Clague Road UCC, 3650 Clague Road, North Olmsted, and volunteers – masked and gloved – will bring a meal to your car. Carol Kovach, cleveland, 26 July 2022 Wintersteen filled the area with seating — a large beige sectional upholstered in performance fabric that curves from the far wall around to the windows and finishes on the other side where the short wall, which meets the back door, ends. Caron Golden, San Diego Union-Tribune, 23 July 2022 The vehicle was described as missing the door guard on the back door of the driver side. Angela Cordoba Perez, The Arizona Republic, 20 July 2022 Recent Examples on the Web: Verb Levin and his allies have asserted that Stevens is backed by groups who also back far-right Republicans, including some congressional Republicans who voted not to certify the 2020 election results. Alexandra Marquez, NBC News, 1 Aug. 2022 LatAm is undergoing a digital transformation and the size of opportunity – both for entrepreneurs and the financial partners that back them – is enormous. Patricia Kemp, Forbes, 18 July 2022 Even those who back the decision on the merits can be surprisingly tentative in their support. Jess Coleman, The New Republic, 8 July 2022 Democrats are encouraging voters ahead of the 2022 midterm elections to support candidates who back stronger gun control. Alexandra Hutzler, ABC News, 7 July 2022 And in theory, users don’t need to trust any of the players in the system, only the technology and the assets that back it. ... Kelvin Chan, The Christian Science Monitor, 30 June 2022 Biden’s victory there, suggesting the Legislature could choose a new slate of electors who would back Trump over Biden. Sarah D. Wire, Los Angeles Times, 23 June 2022 Democrats who back the New York legislation said laws like it are still needed. Maysoon Khan, Anchorage Daily News, 21 June 2022 Lawmakers who back gun control said there was little reason for optimism due to past defeats. Dylan Wells, USA TODAY, 25 May 2022 See More

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.

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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Time Traveler for back

Time Traveler

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

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Statistics for back

Last Updated

4 Aug 2022

Cite this Entry

“Back.” Dictionary, Merriam-Webster, Accessed 15 Aug. 2022.

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More Definitions for back


\ 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 held back tears.
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 walked back and forth



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 : published at an earlier time


backed; backing

Kids Definition of back (Entry 4 of 4)

1 : to give support or help to Which candidate are you backing?
2 : to move backward
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
back up
1 : to move backward
2 : to block or become blocked
3 : to give help or support to
4 : to make a copy of (as a computer file) to protect from being lost

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



Legal Definition of back

1 : being overdue or in arrears back rent
2 : being retroactive especially as compensation reinstated with back pay

Back geographical name

\ ˈbak How to pronounce Back (audio) \

Definition of Back

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

More from Merriam-Webster on back

Nglish: Translation of back for Spanish Speakers

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


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