\ ˈsau̇(-ə)r How to pronounce sour (audio) \

Definition of sour

 (Entry 1 of 3)

1 : being, inducing, or marked by the one of the five basic taste sensations that is produced chiefly by acids and is characteristic of lemon juice sour pickles — compare bitter entry 1 sense 1a, salty entry 1 sense 1b, sweet entry 1 sense 1, umami entry 2
2a(1) : having the acid taste or smell of or as if of fermentation : turned sour milk
(2) : of or relating to fermentation
b : smelling or tasting of decay : rancid, rotten sour breath
c(1) : bad, wrong a project gone sour
(2) : hostile, disenchanted went sour on Marxism
c : not up to the usual, expected, or standard quality or pitch
4 : acid in reaction used especially of soil
5 : containing malodorous sulfur compounds used especially of petroleum products



Definition of sour (Entry 2 of 3)

1a : something sour … they assimilated many Anglo-American sweet pickles and began adding more sugar to their sours.— William Woys Weaver
b : the taste sensation produced chiefly by acids — compare bitter entry 2 sense 1b, salty entry 2, sweet entry 3 sense 2, umami entry 1
2 : a cocktail consisting of a liquor (such as whiskey), lemon or lime juice, sugar, and sometimes ice


soured; souring; sours

Definition of sour (Entry 3 of 3)

intransitive verb

: to become sour

transitive verb

: to make sour

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Other Words from sour


sourish \ ˈsau̇(-​ə)r-​ish How to pronounce sourish (audio) \ adjective
sourly adverb
sourness noun

Synonyms & Antonyms for sour

Synonyms: Adjective

Synonyms: Verb

Antonyms: Verb

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Examples of sour in a Sentence

Adjective The milk had turned sour. He made a sour face. Verb Her disposition has soured in recent years. Jealousy has soured their relationship. His experiences have soured him. The team's victory was soured by an injury to one of their best players.
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Recent Examples on the Web: Adjective On Sunday, Herbert and the new ’do would seem to have an excellent shot at changing his team’s recent sour luck. Jeff Miller, Los Angeles Times, "Chargers’ Justin Herbert hopes he is a cut above against the Jets," 18 Nov. 2020 Soups, stews, and braises are great for using up leftover kimchi that’s been sitting in the fridge for a month or two—that extra sour punch is welcome. Amber Lee, Bon Appétit, "My Fridge Isn’t Complete Without a Massive Jar of Kimchi," 13 Nov. 2020 Like many unemployed residents of Connecticut, Romero is struggling to make ends meet amid a once-booming economy turned sour due to COVID-19. Eliza Fawcett, courant.com, "For these Connecticut workers laid off due to COVID-19, anger and despair fuel a desire for political change," 1 Nov. 2020 This would prove a symbol of how a once-strong relationship nurtured during their karting days turned very sour. Jerome Pugmire, orlandosentinel.com, "Lewis Lewis Hamilton makes F1 history with 92nd victory," 25 Oct. 2020 But his sweet dream has turned awfully sour — thanks to a San Francisco city government that’s wrapped in red tape and often makes even the simplest idea for a small business shockingly complicated. Heather Knight, SFChronicle.com, "Bid to open S.F. ice cream shop turns into a bitter saga because of byzantine small business rules," 2 Oct. 2020 Grant Colfax coming out and saying, ‘This could go really sour, folks. Erin Allday, SFChronicle.com, "San Francisco has handled the coronavirus pandemic well: But at what cost?," 10 Nov. 2020 The Arizona Cardinals' disappointing 34-31 loss to the Miami Dolphins has most fans of the NFL franchise in a sour mood. Jeremy Cluff, The Arizona Republic, "NFL power rankings: Arizona Cardinals have hope after tough loss to Miami Dolphins," 9 Nov. 2020 But sweet, sometimes bitter, sometimes sour oranges can add so much to a cooked dish. Washington Post, "Harness the bright sweetness of oranges in these 7 recipes," 9 Nov. 2020 Recent Examples on the Web: Noun If the weather turns and conditions at the pad (or down-range off the Atlantic coast) sour, NASA and SpaceX are targeting Wednesday, November 18, as a backup date. Jennifer Leman, Popular Mechanics, "LIVE: Watch NASA and SpaceX Launch Four Astronauts Into Space," 15 Nov. 2020 The chain has the Sparkling Pink Warrior cocktail for October made with Three Olives Raspberry Vodka, lemon sour, strawberries, and a lemon wedge, shaken with ice and topped with La Marca Prosecco. Kelly Tyko, USA TODAY, "National Taco Day 2020: Get free tacos, food deals Sunday at Taco Bell, Del Taco, Moe's and more," 2 Oct. 2020 Walsh recommends the sweet-and-sour, cayenne pepper Tiger Sauce as a classic complement to both grilled shrimp and Asian chicken wings. Emmy Favilla, CNN Underscored, "The best hot sauces you can buy online," 14 Sep. 2020 Eastern island cuisine is much spicier and more chile-based, whereas the western island’s food is more sweet-and-sour. Xavier Cousens, WSJ, "Readers’ Favorite Summer Recipes," 4 Sep. 2020 For fans, the allure of a sour comes in its uniquely tangy aroma and taste. Ryan Prior, CNN, "Sour beer: The chemistry behind this wondrously complex craft brew," 18 Aug. 2020 This mellow sour has restrained fruit and a bit of dryness. Marc Bona, cleveland, "13 beers to try in July (photos)," 5 July 2020 Tourist investors are known to be flightier than others when venture capital sours. Lucinda Shen, Fortune, "Is this the flight of the tourist investor?," 14 Apr. 2020 For dessert, sticky toffee pudding with passionfruit caramel sauce, paired with Frog Weiss, a fruited sour. Carol Deptolla, Milwaukee Journal Sentinel, "Third Space and Shully's are having a virtual beer dinner on May 2," 29 Apr. 2020 Recent Examples on the Web: Verb Fast-food work is stressful: chronic understaffing, hot grease, time clocks monitoring your breaks, enough unkind customers to sour a whole night. Richard Renaldi, The New Yorker, "Faces of a Fast-Food Nation," 23 Nov. 2020 The relationship between rap and Trump began to sour after Trump launched his political career by using the racist birther conspiracy to attack President Barack Obama, a man who by then had surpassed Trump as a hip-hop icon. Washington Post, "Some famous rappers backed Trump’s campaign. Did it matter?," 20 Nov. 2020 The Trump team's mood continued to sour as late counting gave Biden wins in Wisconsin and Michigan. David Jackson, USA TODAY, "Donald Trump's aides are increasingly gloomy – and mad at other GOP officials," 6 Nov. 2020 The trickiest part of U.S. antitrust law is predicting at what point something good for consumers could sour, legal experts said. Dallas News, "The government kept to the sidelines as Google got big. Will it be able to rein it back in?," 15 Oct. 2020 One big fear is that consumers’ credit quality could begin to sour if Congress doesn’t reach a deal on additional aid for the unemployed. Annamaria Andriotis, WSJ, "Coronavirus Tanked the Economy. Then Credit Scores Went Up.," 18 Oct. 2020 Such an outcome could also sour relations between the EU and its closest ally in foreign and security policy and have knock-on effects in areas ranging from aviation to finance and scientific research. Tim Ross, Bloomberg.com, "Johnson Tells Merkel That Gaps Remain With EU as Time Runs Short," 11 Oct. 2020 The leaders of many local companies are starting to sour on remote work, said Angela Farley, chief operating officer of the Dallas Regional Chamber. Dallas News, "The pandemic disrupted work in North Texas for good, and not always for the better," 11 Oct. 2020 But Trump had begun to sour on him earlier this year as Parscale attracted a wave of media attention that included focus on his seemingly glitzy lifestyle on the Florida coast that kept him far from campaign headquarters in Virginia. Jonathan Lemire, Anchorage Daily News, "Former Trump campaign boss hospitalized in Florida after threatening to harm self," 28 Sep. 2020

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'sour.' 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 sour


before the 12th century, in the meaning defined at sense 1


before the 12th century, in the meaning defined at sense 1a


14th century, in the meaning defined at intransitive sense

History and Etymology for sour


Middle English, from Old English sūr; akin to Old High German sūr sour, Lithuanian sūrus salty

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Time Traveler for sour

Time Traveler

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

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Statistics for sour

Last Updated

24 Nov 2020

Cite this Entry

“Sour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sour. Accessed 1 Dec. 2020.

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More Definitions for sour

How to pronounce sour (audio)

English Language Learners Definition of sour

 (Entry 1 of 3)

: having an acid taste that is like the taste of a lemon
: having the unpleasant taste or smell of food that is no longer fresh
: unpleasant or unfriendly



English Language Learners Definition of sour (Entry 2 of 3)

: an alcoholic drink that has a sour taste



English Language Learners Definition of sour (Entry 3 of 3)

of food : to lose freshness and get an unpleasant taste or smell : to become sour
: to become unpleasant or unfriendly
: to make (someone or something) unpleasant or unfriendly
\ ˈsau̇r How to pronounce sour (audio) \
sourer; sourest

Kids Definition of sour

 (Entry 1 of 2)

1 : having an acid or tart taste a sour fruit
2 : having spoiled : not fresh sour milk
3 : suggesting decay a sour smell
4 : not pleasant or friendly a sour look

Other Words from sour

sourly adverb He looked at me sourly enough but said nothing. — Robert Louis Stevenson, Treasure Island


soured; souring

Kids Definition of sour (Entry 2 of 2)

1 : to make or become acid or tart in taste (as by spoiling) The milk soured.
2 : to lose or cause to lose interest or enthusiasm He soured on trying new stunts following the mishap.
3 : to harm or damage The misunderstanding soured their friendship.
\ ˈsau̇(ə)r How to pronounce sour (audio) \

Medical Definition of sour

 (Entry 1 of 2)

: causing, characterized by, or being the one of the four basic taste sensations that is produced chiefly by acids — compare bitter, salt entry 2 sense 2, sweet entry 1

Other Words from sour

sourness noun



Medical Definition of sour (Entry 2 of 2)

: the primary taste sensation produced by acid stimuli

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