\ 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 Ole Miss got back in front against Kentucky on a 26-yard field goal from Jonathan Cruz with 2:19 remaining in the third quarter. The Courier-Journal, 1 Oct. 2022 Catonsville led 13-6 in the second quarter and got the ball back on a Franklin punt. Craig Clary, Baltimore Sun, 1 Oct. 2022 Power is coming back slowly to homes and businesses in Florida, South Carolina, North Carolina and southern Virginia, according to data from Leila Sackur, NBC News, 1 Oct. 2022 The crowd got back into the game eventually, and the Bengals were excited as ever in the locker room after the win to lift them to .500 once again. Andrew Gillis, cleveland, 30 Sep. 2022 So the question, in this case, is which of the players the Jazz got back will be part of the long-term solution. Eric Walden, The Salt Lake Tribune, 30 Sep. 2022 Boise State got the ball back and took a 14-13 lead with 4:43 remaining. Kirk Kenney, San Diego Union-Tribune, 30 Sep. 2022 Jackson got back on track with a win on the road against the patriots, while Allen and the Bills suffered their first loss last week against the Dolphins. Richard Morin, USA TODAY, 30 Sep. 2022 Another thing to watch in the oil market: Gridlock is coming back. Dan Molinski, WSJ, 30 Sep. 2022 Recent Examples on the Web: Adjective Those who suffer from back pain can look for a mattress with pressure-relieving foam or a combination of plush foam and coils. Amanda Constantine, Good Housekeeping, 28 Sep. 2022 Federer spent a few years in the wilderness, dealing with back pain, and a loss of confidence. Louisa Thomas, The New Yorker, 24 Sep. 2022 To make matters worse, Patriots quarterback Mac Jones will be playing through back pain against an excellent Steelers defense. Doug Ziefel, Chicago Tribune, 18 Sep. 2022 The TikTok dance version goes something like this: One person in a group fakes everyone out by falling to the ground with back pain. Brahmjot Kaur, NBC News, 16 Sep. 2022 For years, Ver Kuilen ran on a prosthesis made for walking, which broke frequently and caused her back pain. Allison Torres Burtka, Outside Online, 16 Sep. 2022 Daly has long been open about suffering from chronic lower back pain. Giovana Gelhoren, Peoplemag, 15 Sep. 2022 Manuela Smith, who has dementia and has been missing for a little more than two weeks, was treated for back pain at Scripps Mercy Hospital in Hillcrest during the Labor Day Weekend and later released, her family said. David Hernandez, San Diego Union-Tribune, 12 Sep. 2022 Futuristic military dreams of an Iron Man exoskeleton suit might be giving way for something simpler: a lightweight wearable to help with back pain. Pranshu Verma, Washington Post, 10 Sep. 2022 Recent Examples on the Web: Verb The elections on Sunday were put in motion when the government of Prime Minister Mario Draghi collapsed in July after several parties, including Meloni’s, refused to back his coalition in a confidence vote. Tom Kington And Tracy Wilkinson, Anchorage Daily News, 25 Sep. 2022 The elections on Sunday were put in motion when the government of Prime Minister Mario Draghi collapsed in July after several parties, including Meloni’s, refused to back his coalition in a confidence vote. Tom Kington, Los Angeles Times, 22 Sep. 2022 Additionally, the other system this bet fits is to back the underdog in games with a low total. Nick Hennion, Chicago Tribune, 19 Sep. 2022 Aware of this history, Brazil’s economic elite still chose to back Bolsonaro in the 2018 elections, supporting the fraudulent arrest that year of President Luiz Inácio Lula da Silva that would bar him from the race. Time, 16 Sep. 2022 That means bettors can back a favorite in pursuit of a safer profit or swing for the fences on an underdog. Xl Media, cleveland, 8 Sep. 2022 The White House is also asking Congress for an additional $47.1 billion in emergency funding for Covid-19 and monkeypox and to back Ukraine in the war with Russia, as well as spending for natural disasters, according to administration officials. Natalie Andrews, WSJ, 4 Sep. 2022 Healey later broke with most party leaders to back Representative Ayanna Pressley in her 2018 upset of Michael Capuano, endorsing Pressley after the then-city councilor had done the same for her four years earlier. Matt Stout,, 28 Aug. 2022 Western financiers with piles of cash are typically unwilling to back African startups in those early stages, when the future—and the potential to scale—remain uncertain. Aanu Adeoye, Quartz, 21 July 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 7 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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