\ ˈthin How to pronounce thin (audio) \
thinner; thinnest

Definition of thin

 (Entry 1 of 3)

1a : having little extent from one surface to its opposite thin paper
b : measuring little in cross section or diameter thin rope
2 : not dense in arrangement or distribution thin hair
3 : not well fleshed : lean
4a : more fluid or rarefied than normal thin air
b : having less than the usual number : scanty thin attendance
c : few in number : scarce
d : scantily supplied
e : characterized by a paucity of bids or offerings a thin market
5a : lacking substance or strength thin broth a thin plot
b of a soil : infertile, poor
6a : flimsy, unconvincing a thin disguise
b : disappointingly poor or hard had a thin time of it
7 : somewhat feeble, shrill, and lacking in resonance a thin voice
8 : lacking in intensity or brilliance thin light
9 : lacking sufficient photographic density or contrast
thin on the ground


thinned; thinning

Definition of thin (Entry 2 of 3)

transitive verb

: to make thin or thinner:
a : to reduce in thickness or depth : attenuate
b : to make less dense or viscous
c : dilute, weaken
d : to cause to lose flesh thinned by weeks of privation
e : to reduce in number or bulk

intransitive verb

1 : to become thin or thinner
2 : to become weak


thinner; thinnest

Definition of thin (Entry 3 of 3)

: in a thin manner : thinly used especially in combination thin-cladthin-flowing

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Other Words from thin


thinly adverb
thinness \ ˈthin-​nəs How to pronounce thinness (audio) \ noun
thinnish \ ˈthi-​nish How to pronounce thinnish (audio) \ adjective

Synonyms & Antonyms for thin

Synonyms: Adjective

bony (also boney), fatless, lean, lithe, skinny, slender, slim, spare, svelte

Synonyms: Verb

adulterate, cut, dilute, extend, lace, sophisticate, water down, weaken

Antonyms: Adjective

chubby, corpulent, fat, gross, obese, overweight, plump, portly, rotund, tubby

Antonyms: Verb

enrich, fortify, richen, strengthen

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Choose the Right Synonym for thin


thin, slender, slim, slight, tenuous mean not thick, broad, abundant, or dense. thin implies comparatively little extension between surfaces or in diameter, or it may imply lack of substance, richness, or abundance. thin wire a thin soup slender implies leanness or spareness often with grace and good proportion. the slender legs of a Sheraton chair slim applies to slenderness that suggests fragility or scantiness. a slim volume of poetry a slim chance slight implies smallness as well as thinness. a slight build tenuous implies extreme thinness, sheerness, or lack of substance and firmness. a tenuous thread

Examples of thin in a Sentence


a thin coating of dust pizza with a thin crust a thin slice of ham a thin stand of trees


He added a little more water to thin the gravy. The haze thinned in the late afternoon. His face has been thinned by illness.


She sliced the cheese thin.
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Recent Examples on the Web: Adjective

In extreme cold, a soldier would pair the M-43 with multiple thin layers underneath. Rachel S. Gross, The Atlantic, "The Military Origins of Layering," 15 Sep. 2019 The rugged terrain on seamounts and the challenge of peeling off a thin layer of crust mean they won't be exploited anytime soon. Warren Cornwall, Science | AAAS, "Mountains hidden in the deep sea are biological hot spots. Will mining ruin them?," 12 Sep. 2019 Lungs—and subsequently the rest of the body—are protected from these contaminants by a thin layer of lipids that coat the lungs and some very important cells called macrophages. Wired, "Vaping May Hamper the Lungs' Ability to Fend off Infections," 4 Sep. 2019 Usually, the ammonia clouds are the top thin layer of both the brown and white clouds that make up Jupiter's bands. Fox News, "Intense ammonia storms on Jupiter are messing up the planet's belts," 4 Sep. 2019 For example, with peanut butter (or other spreads), put a thin layer on each slice of bread, with the jelly or other wet ingredient in the middle. Madelyn Fernstrom, NBC News, "Dr. Fernstrom: 7 healthy (and fun) back-to-school lunch hacks," 3 Sep. 2019 Build the mask up with thin layers, as opposed to glopping it all on at once, to avoid excessive goopiness. Andrea Cheng, Condé Nast Traveler, "The Best Skin Care Routine For Your Next Flight: A Step-By-Step Guide," 30 Aug. 2019 For the experiment, the researchers created a thin layer of metal using a process called physical vapor deposition, which involved turning iron into a vapor and condensing it on a glass surface. Emily Matchar, Smithsonian, "Could a Rusty Bridge Generate Electricity?," 26 Aug. 2019 Across the region, the Forest Service is devising projects to thin and burn on the Sagehen model. Nicola Twilley, The New Yorker, "A Trailblazing Plan to Fight California Wildfires," 19 Aug. 2019

Recent Examples on the Web: Verb

The farm system, thinned by the trades Dombrowski made, is one of the leanest in baseball. Tom Verducci,, "Why the Red Sox Fired Dave Dombrowski After He Delivered a Championship," 9 Sep. 2019 But at the one-hour mark, the Expo Center crowd began to thin out. CBS News, "Trump rallies supporters in North Carolina ahead of special election," 9 Sep. 2019 State officials and marijuana industry sources said black-market dealers appear to be using new substances to thin out THC oil, which is thick, odorless and colorless. Author: Lena H. Sun, Laurie Mcginley, Anchorage Daily News, "As vaping-related lung illnesses spike, investigators eye contaminants," 30 Aug. 2019 Just when the crowd started to thin out, Simon doubled back to his guitars and picked another acoustic one up. Hilary Hughes, Billboard, "Paul Simon Surprises With Moving Bob Weir Duet During Hit-Laden Closing Set at Outside Lands," 12 Aug. 2019 The smoothie pops are made with Greek yogurt thinned out with a little coconut milk and sweetened with some honey. Carrie Knauer,, "Carrie’s Kitchen: Summer recipes inspired by the tropics," 22 July 2019 Letting private companies make money off of timber harvests that also serve to thin out overgrown forests, restoring them to a healthier state, would help accomplish this goal. Umair Irfan, Vox, "Ryan Zinke blamed environmentalists for California’s massive wildfires. Again.," 21 Nov. 2018 With the next debate looming, the field of Democratic presidential candidates is thinning fast, down from an eye-popping 23., "“It’s a necessity of politics that you be on Facebook now,” said Matt Corridoni, press secretary to US Representative Seth Moulton’s unsuccessful presidential run. “Republicans are doing the same thing.”," 12 Sep. 2019 One of Antarctica’s biggest and most unstable glaciers is thinning faster than scientists had realized, with one of its key ice shelves losing up to 33 percent of its ice over a 30-year period ending in 2009. Denise Chow, NBC News, "Antarctica's Thwaites Glacier may be thinning faster than previously thought," 10 Sep. 2019

Recent Examples on the Web: Adverb

Still, the Longhorns are paper thin at a position that was expected to be rock solid. Nick Moyle,, "Texas’ Jordan Whittington last RB standing as injuries mount," 23 Aug. 2019 The volume of new series being produced means that talent and resources are spread thin, and also that networks and streaming platforms have less to lose from commercial flops. Adam Wilson, Harper's magazine, "Good Bad Bad Good," 16 Sep. 2019 The Ravens lost Smith and Terrell Suggs in free agency, leaving their defense notably thin on the edges. Childs Walker,, "Nothing comes easily for an NFL rookie, and Ravens linebacker Jaylon Ferguson wouldn’t have it any other way," 13 Aug. 2019 Rob Thomas was stretched thin, between the final season of iZombie and the new season of Veronica Mars. Jennifer Ouellette, Ars Technica, "Review: iZombie sets up strong fifth season, then whiffs the series finale," 5 Aug. 2019 But Orange County shows no signs of slowing its growth which can be a problem for the county’s more rural areas where firefighter coverage is stretched thin. Joe Mario Pedersen,, "Orange County fire chief’s first two months: putting out fires and preparing for more," 7 Aug. 2019 While the likes of Facebook and Amazon have nearly unlimited budgets for litigation and lobbying, the agency is stretched thin. Jeff John Roberts, Fortune, "How Facebook’s $5 Billion Fine Should Be Spent," 20 July 2019 Police officials said their force had been spread thin by a protest march that took place earlier that day in a different part of Hong Kong. Austin Ramzy,, "Hong Kong police ban a march to protest mob violence," 25 July 2019 Reports from friends whose homes are in danger tell me that Alaska’s many amazing firefighters are innovative and persistent as always, yet spread thin across the state. Alli Harvey, Anchorage Daily News, "As Alaska burns, acts of caring — for yourself, and for others — might save your sanity," 11 July 2019

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


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


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


13th century, in the meaning defined above

History and Etymology for thin


Middle English thin, thinne, going back to Old English þynne, going back to Germanic *þunnu- (assimilated to the -ja-stem adjectives in West Germanic, whence Middle Dutch dunne "thin," Old High German dunni, against Old Norse þunnr), generalized from a paradigm *þenu-, *þunw-a-, going back to Indo-European *ténh2u-, *tn̥h2u̯ó-, whence also, from with a base *tenh2u-, *tn̥h2u- with varying ablaut and suffixation, Old Irish tanae "thin, slender," Old Welsh teneu, Middle Breton tanau, Latin tenuis "fine-drawn, thin, narrow, slight," Greek tanu- "extended, long," tanaós "outstretched, long," Old Church Slavic tĭnŭkŭ "fine, delicate," Russian tónkij "thin," Croatian & Serbian tȁnak, Lithuanian tę́vas, Sanskrit tanúḥ, tánukaḥ "thin, small"

Note: Indo-European *tenh2u-, *tn̥h2u- is usually taken to be a derivative of the verbal base *ten- "stretch, extend"; see tenant entry 1.


Middle English thinnen, going back to Old English þynnian, derivative of þynne thin entry 1


Middle English thynne, derivative of thin, thinne thin entry 1

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Statistics for thin

Last Updated

18 Oct 2019

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Time Traveler for thin

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

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More Definitions for thin



English Language Learners Definition of thin

 (Entry 1 of 3)

: having a small distance between the top and bottom or front and back surfaces : not thick
: not having a lot of extra flesh on the body : not fat
: not growing closely together : not growing in a large amount



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

: to become less crowded, close together, or full
: to make (a liquid) less thick by adding water or some other liquid to it
of a person's hair : to become less thick as more hairs fall out over time



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

: in a way that makes thin pieces, layers, etc.


\ ˈthin How to pronounce thin (audio) \
thinner; thinnest

Kids Definition of thin

 (Entry 1 of 2)

1 : having little body fat
2 : having little size from one surface to its opposite : not thick a thin board
3 : having the parts not close together thin hair
4 : flowing very easily a thin soup
5 : having less than the usual number Attendance was thin.
6 : not very convincing a thin excuse
7 : somewhat weak or high a thin voice
8 : having less oxygen than normal thin air

Other Words from thin

thinly adverb
thinness noun


thinned; thinning

Kids Definition of thin (Entry 2 of 2)

: to make or become smaller in thickness or number The crowd was beginning to thin.

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More from Merriam-Webster on thin

Rhyming Dictionary: Words that rhyme with thin

Thesaurus: All synonyms and antonyms for thin

Spanish Central: Translation of thin

Nglish: Translation of thin for Spanish Speakers

Britannica English: Translation of thin for Arabic Speakers

Comments on thin

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


involving a confidence or trust

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