\ˈsau̇(-ə)r \

Definition of sour 

(Entry 1 of 3)

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

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

3a : unpleasant, distasteful

b : cross, sullen

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

b : the primary taste sensation produced by acid stimuli

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 \ adjective
sourly adverb
sourness noun

Examples of sour in a Sentence


The milk had turned sour. He made a sour face.


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

Irish-Jewish relations haven't always been this sour. Sean Savage, Jewish Journal, "Ireland goes ahead with legislation to boycott products made in Israeli settlements," 12 July 2018 The songs were strong; unfortunately, Sweet’s vocals were sour. Milwaukee Journal Sentinel, "Best and worst of Summerfest Day 2: Marshmello, Nelly, Tory Lanez, Buckcherry and more," 28 June 2018 Things go sour, of course — when everyone's at least partially a bad guy, things are going to get ugly. Bill Goodykoontz, azcentral, "'Sicario: Day of the Soldado' lacks ambition of the original," 28 June 2018 Cornhole event turns sour as brawl breaks out Advertisement A fundraising event at Foxhall Resort in Douglas County, Georgia, went disastrously wrong when its cornhole tournament led to a brawl among participants. Kaitlyn Schwers, kansascity, "Parents beat a man to death, Missouri sheriff says. They said he had hit their son," 12 June 2018 There’s now a restaurant that serves a single main dish, a Sichuan hot-and-sour fish soup. Jim Thurman, Los Angeles Magazine, "A China Chain’s Pricey Bowls of Sauerkraut Fish Soup Have Landed in the SGV," 24 May 2018 Murphy has a long memory, sources say, so when the front-runner Lamont picked Bysiewicz as his running mate earlier this week, Murphy was sour about the choice. Neil Vigdor,, "Chris Murphy Exerts Power Over The Democratic Ticket," 18 May 2018 Of the latter, the hot and sour rendition lacked the hallmark vinegar base and instead tasted as though egg drop soup had found its way into the bowl. Anna Caplan, star-telegram, "It's difficult to choose a favorite dish at the impressive Thai Orange | Fort Worth Star-Telegram," 1 May 2018 Hot and sour soup ($17) is ubiquitous on many Chinatown menus but deconstructed here. Michael Bauer, San Francisco Chronicle, "Mister Jiu’s fulfills its vision with 3½ stars," 11 Apr. 2018

Recent Examples on the Web: Noun

With the pickleball courts on their third day of being out of service due to some repairs to the fence, Murphy is on this day, well, more than a little half-sour. Amy S. Rosenberg,, "Ocean City and the most cutthroat pickleball game at the Jersey Shore," 11 July 2018 The bar has also experimented with a cauliflower sour, says DORO Restaurant Group partner Scott Miller. Leeanne Griffin,, "Beyond Bloody Marys: Drinking Your Veggies At Your Favorite Cocktail Bar," 23 Jan. 2018 Which nations will feel the sweetness of joy and which the sour of despair? Jared Young,, "Own goals are having a big impact in the 2018 World Cup," 21 June 2018 Guests sample 5 rare sour & funky beers from Rhinegeist cellars, including newest sour ale of dark descent. Rasputin Todd,, "Things to do in Cincinnati this week: June 18-24," 18 June 2018 The most popular brews include juicy, low-bitterness IPAs and fruity sherbet sours. Robert Allen, Detroit Free Press, "Purple beer helps this Ann Arbor brewery draw national attention," 31 May 2018 Consider that fruit-forward sours can often bridge the gap between wine and beer. Kathy Flanigan, Milwaukee Journal Sentinel, "A summer (and fall) guide to beer and cider festivals," 14 May 2018 Plant some Mexican sour gherkin cucumbers or blue borage. Anne Brockhoff, kansascity, "Is your cocktail in season? Bartenders letting gardens dictate what's in your glass," 24 Apr. 2018 His defining trait, and the one Mr. Raz plays best, is his sour, surly implacability. Mike Hale, New York Times, "Review: ‘Fauda’ Returns on Netflix, Guns Blazing," 23 May 2018

Recent Examples on the Web: Verb

Republicans will be making the case to the administration that the tariffs could dampen the economic gains from the GOP tax cuts and sour the mood among voters as lawmakers are campaigning to protect the Republican majority in Congress. Lisa Mascaro, The Seattle Times, "Congress faces immigration showdown, tension on tariffs," 3 June 2018 That stadium fight eroded FC Cincinnati's seemingly unstoppable momentum coming out of 2017, and maybe even soured some in MLS on Cincinnati. Patrick Brennan,, "After stadium progress, what's next for FC Cincinnati's MLS expansion push?," 17 Apr. 2018 Oil headed for its worst week in more than a month after U.S. President Donald Trump called for tariffs on more Chinese goods, souring investor optimism that tensions between the world's two largest economies will ease with negotiations. Grant Smith, Houston Chronicle, "Oil thwarted by trade war fears as Trump doubles down of tariffs," 6 Apr. 2018 Chinese banks began lowering the amount of cash they are required to set aside as early as the first quarter of 2016, when a tide of souring corporate loans brought profit levels near zero across the industry. Chao Deng And Chuin-wei Yap, WSJ, "China Lowers Banks’ Liquidity Requirement," 6 Mar. 2018 But his remarks could be seen as a message to Washington over souring relations with Moscow, including U.S. investigations into Russian meddling in the 2016 presidential election. Author: Anton Troianovski, Anchorage Daily News, "Putin displays new weapons and issues warning to U.S. and Europe," 1 Mar. 2018 This domestic thriller touches on racial and economic tensions, women’s ambitions and souring family dynamics. Joumana Khatib, New York Times, "Paperback Row," 5 Jan. 2018 The bet soured when U.S. interest rates plummeted, sticking the city with a $50 million-per-year bill. Tresa Baldas, Detroit Free Press, "Kwame Kilpatrick: Detroit bankruptcy wasn't my fault," 15 June 2018 But the mood could easily sour if talks with the North go wrong. The Economist, "South Korea’s ruling party wins a landslide victory in local elections," 14 June 2018

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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Learn More about sour

Dictionary Entries near sour

soup to nuts

soup up



sour ball



Phrases Related to sour

on a sour note

sour on

soured cream

Statistics for sour

Last Updated

8 Oct 2018

Look-up Popularity

Time Traveler for sour

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

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More Definitions for sour



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 \
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
sourness noun


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 \

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 sense 2, sweet

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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Comments on sour

What made you want to look up sour? Please tell us where you read or heard it (including the quote, if possible).


lying above or upon

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