\ 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 The pulp itself is sweet and sour, with citrusy notes. Washington Post, "5 recipes featuring tangy, puckery tamarind — from pad thai to a glaze for poultry," 10 Sep. 2020 Booze lovers have since been coming for rotating microbrews of rare sour and barrel-aged beers, as well as their extensive top-shelf liquor selection that includes Pappy Van Winkle whiskeys and 15 types of fernet. Amanda Albee, Dallas News, "Strangeways Dallas reopens after being reclassified as a restaurant by the TABC," 23 Sep. 2020 But like so many other weeks, the week turned sour over Trump’s words. Paul Bedard, Washington Examiner, "White House Report Card: One step forward, two steps back," 12 Sep. 2020 Other companies also have headed to court as deals turned sour. Nina Trentmann, WSJ, "Deals Are Being Dropped as Buyers Turn Wary During the Pandemic," 11 Sep. 2020 Then something unexpected intrudes, the stench of something sour and stale. Hannah Michell, SFChronicle.com, "The problem of online dating exposed in Hannah Michell’s ‘IRL’," 6 Sep. 2020 In his new role, Hall’s duties will include overseeing the brewery’s sales team, providing creative input into its graphics and taproom decor, and spearheading its initial foray into sour and barrel-aged products. Matt Koesters, The Enquirer, "Let's experiment with beer floats, because why not?," 2 July 2020 The apricot-lime glaze, with a touch of hot sauce, makes the perfect combo of sweet, sour, and spicy. Woman's Day Kitchen, Woman's Day, "Apricot-Glazed Chicken and Corn," 29 June 2020 Bieber's outing did end on a sour note after he was left in with a 10-run lead in the eighth. Noah Trister, Star Tribune, "Ramirez helps Indians snap skid with 10-3 win over Tigers," 17 Sep. 2020 Recent Examples on the Web: Noun 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 Banks — say, Deutsche Bank — usually have to take special care with loans that are turning sour. Meg Cramer, ProPublica, "Yes, Trump Hotels Do Appear to Qualify for Coronavirus Bailout Benefits.," 8 Apr. 2020 Recent Examples on the Web: Verb 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 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 And Terry Spencer, chicagotribune.com, "President Trump’s former campaign manager hospitalized amid threat to harm himself," 28 Sep. 2020 But efforts to mollify the Chinese government could easily sour US regulators on any deal. Timothy B. Lee, Ars Technica, "Oracle, one of Donald Trump’s favorite companies, wins TikTok deal," 13 Sep. 2020 Sunday still looks like the warmest day with a chance of 80s central and southern Minnesota, but skies may sour quickly on Labor Day, especially PM hours. Paul Douglas, Star Tribune, "Mostly Lake-Worthy Into Sunday, But Labor Day Weather Quickly Sours," 3 Sep. 2020 Last year, Hawaii, a state of 1.5 million people, hosted 10.4 million visitors and those unsustainable numbers have started to sour the aloha spirit. Jen Murphy, Condé Nast Traveler, "When Travel Restarts, Hawaiians Are Hoping for a More Respectful Future," 18 June 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

19 Oct 2020

Cite this Entry

“Sour.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/sour. Accessed 23 Oct. 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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