\ 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

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

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 had his hands behind his back. a bird with a dark 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 But that support was prefaced on Republicans contracting mass amnesia about Manchin stabbing them in the back to allow the Inflation Reduction Act to pass. The Editors, National Review, 30 Sep. 2022 Two have tempered glass doors and all come with adjustable shelving and traditional hardware, plus there are ports in the back for cord management, and the stand can hold a maximum of 250 pounds. Rachel Klein, Popular Mechanics, 29 Sep. 2022 So Port and his staff at Better Records sit for hours in a windowless room, unplug the small refrigerator in the back so as not to get any electrical interference, and simply listen. Geoff Edgers, Washington Post, 29 Sep. 2022 These cabinets tend to be cavernous, resulting in items getting stuck (and subsequently lost) in the back. Mary Cornetta, Better Homes & Gardens, 29 Sep. 2022 Seattle's new-ish scheme, which starts with a 3-4 up front and split safeties in the back, hasn't yielded many successful results to this point. Tony Garcia, Detroit Free Press, 29 Sep. 2022 Even Shakespeare’s Brutus felt compelled to stab Julius Caesar in the back. Will Self, Harper’s Magazine , 28 Sep. 2022 Jennings can be seen in the back on keyboards, while Carlile prowls the stage and sings beautiful harmony with her backup singers. Jon Freeman, Rolling Stone, 28 Sep. 2022 The new j7 looks just like the old j7 with a camera in the front, a big dust bin in the back, and a bottom layout that is almost identical to the old bot. Ron Amadeo, Ars Technica, 27 Sep. 2022 Recent Examples on the Web: Adverb The lights were back on in Hot Spring County by around 2:30 p.m. on Monday, after an early morning outage left nearly 4,000 Entergy customers without power, according to the utility. Alexandria Brown, Arkansas Online, 20 Sep. 2022 Chicago won in overtime when Browns QB Tim Couch threw an interception that was run back for a TD. Terry Pluto, cleveland, 19 Sep. 2022 The Orb — a gold globe featuring a cross — is intended to symbolize that the monarch's power comes from God, and dates back to 1661. Abigail Adams, Peoplemag, 19 Sep. 2022 The Kremlin’s top spokesman, Dmitry Peskov, on Monday did push back against new allegations of war crimes against Russian troops, which emerged in recent days in Izyum and other Ukrainian cities liberated in Kharkiv. David L. Stern, Washington Post, 19 Sep. 2022 The Queen's funeral carriage was drawn from new Royal Navy recruits, a tradition dating back to Queen Victoria's funeral in 1901, when the Navy stepped in after horses drawing her coffin missbehaved. WSJ, 19 Sep. 2022 Running back Aiden Ramos of Bishop Amat has committed to Cal Poly. . . . Eric Sondheimer, Los Angeles Times, 19 Sep. 2022 Omar asked his contact to hold it back, as one of the final lots of the sale, so that the room would be quieter. Sam Knight, The New Yorker, 19 Sep. 2022 Queen Elizabeth II presented the piece of jewelry to Meghan in honor of their first solo outing together back in 2018, according to People. Chelsey Sanchez, Harper's BAZAAR, 19 Sep. 2022 Recent Examples on the Web: Adjective Attacking the back line of Howard’s defense, Flotildes fired four straight aces. Jacob Steinberg, Baltimore Sun, 20 Sep. 2022 Injuries also have shaken up the Americans’ back line. Kevin Baxter, Los Angeles Times, 20 Sep. 2022 On May 11, 2022, Moriah’s friend went out for the evening – leaving Moriah on her own in the tiny apartment above a garage in a back alley. Dateline Nbc, NBC News, 20 Sep. 2022 Yumika Bady, 25, was also at her home across the street and saw that the blast blew out the back window of her car that was parked nearby. Don Babwin, ajc, 20 Sep. 2022 During the incident, Mr. Ramsey punched through the back windshield of the other individual’s Subaru, the report said. Jesse Newman, WSJ, 20 Sep. 2022 Porsche isn't alone in scaling back valuation targets, with Intel lowering expectations for its Mobileye. Monica Raymunt,, 19 Sep. 2022 Oldroyd has dealt with some lingering back issues throughout his career. Kevin Reynolds, The Salt Lake Tribune, 19 Sep. 2022 His followers, commanded to raise their fingers in salute, did so—resulting in a scene that looked like it was freshly plucked from Leni Riefenstahl’s back catalogue. Alex Shephard, The New Republic, 19 Sep. 2022 Recent Examples on the Web: Verb The final piece of the scheduling puzzle — where the conference’s TV partners select games and move some up or back a day — is expected to be completed later this month. Mark Zeigler, San Diego Union-Tribune, 13 Sep. 2022 The only way to correct this issue on my testing rig was to alt-tab the game to Windows and back a few times. Sam Machkovech, Ars Technica, 22 Aug. 2022 Republicans will determine which candidate will likely succeed longtime retiring Sen. Richard Shelby in the Alabama Senate runoff, a race that has seen Trump endorse one candidate only to withdraw the endorsement and back his opponent. Dylan Wells, USA TODAY, 20 June 2022 The antiaging antioxidant is one of the few skin-care ingredients dermatologists will back for its noticeable brightening, protective, and firming properties, as well as its ability to boost collagen production—which has a plumping effect. Glamour, 9 June 2022 Pressing the button can do things like turning the volume up, powering the earbuds on and off, going forward a track or back a track, and more. Chris Hachey, BGR, 17 May 2022 Conservative radio host Howie Carr’s decision to back Chris Doughty and turn on Geoff Diehl, a longtime ally and fellow Donald Trump supporter, potentially portends a still-shifting race. Globe Staff,, 6 Sep. 2022 Yet even though the FBI has found no evidence to back these claims, and The Washington Times ultimately issued a correction to the article, the disinformation is still widely accessible with a simple Google search. Wired, 18 Aug. 2022 Trump and his allies have denounced the search as unlawful and politically motivated, but provided no evidence to back that up and have refused to share a copy of the warrant with the public. Perry Stein, Washington Post, 11 Aug. 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

3 Oct 2022

Cite this Entry

“Back.” Dictionary, Merriam-Webster, Accessed 3 Oct. 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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