thin

1 of 3

adjective

thinner; thinnest
Synonyms of thinnext
1
a
: 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
4
a
: 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
5
a
: lacking substance or strength
thin broth
a thin plot
b
of a soil : infertile, poor
6
a
: 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
thinly adverb
thinness noun
thinnish adjective
see also:

thin

2 of 3

verb

thinned; thinning

transitive verb

: to make thin or thinner:
a
: to reduce in thickness or depth : attenuate
b
: to make less dense or viscous
c
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

thin

3 of 3

adverb

thinner; thinnest
: in a thin manner : thinly
used especially in combination
thin-clad
thin-flowing
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

Adjective a thin coating of dust pizza with a thin crust a thin slice of ham a thin stand of trees Verb He added a little more water to thin the gravy. The haze thinned in the late afternoon. His face has been thinned by illness. Adverb She sliced the cheese thin.
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Adjective
If these results hold up in future missions, atom-thin electronics could transform spacecraft design. Rupendra Brahambhatt, Interesting Engineering, 21 Feb. 2026 The near side has a thin crust, low topography and KREEP, a geochemical component rich in heat-producing radioactive elements. Ashley Strickland, CNN Money, 21 Feb. 2026
Verb
With margins thinning, Kindred had no choice but to pass those higher costs on to her customers. Diamond Vences, Charlotte Observer, 20 Feb. 2026 One solution to thin out the plants was to let a herd of 400 goats to clear dense undergrowth. Emily Holshouser, Fort Worth Star-Telegram, 19 Feb. 2026
Adverb
Donor countries' budgets are spread thin among humanitarian emergencies around the world, including famine in Sudan and the wars in Gaza and Ukraine. ABC News, 18 Feb. 2026 Around the world, education systems are stretched thin. José Manuel Barroso, Fortune, 17 Feb. 2026 See All Example Sentences for thin

Word History

Etymology

Adjective

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.

Verb

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

Adverb

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

First Known Use

Adjective

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

Verb

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

Adverb

13th century, in the meaning defined above

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

Cite this Entry

“Thin.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/thin. Accessed 23 Feb. 2026.

Kids Definition

thin

1 of 2 adjective
thinner; thinnest
1
: having little extent from one surface to its opposite
thin paper
2
: having widely scattered units
thin hair
3
: having too little flesh
a tall thin boy
4
: less dense than normal
thin air
5
: lacking substance or strength
thin broth
thin excuses
6
: somewhat weak or shrill
a thin voice
thinly adverb
thinness noun

thin

2 of 2 verb
thinned; thinning
1
: to make or become thin
2
: to reduce in number especially to prevent crowding
thin young carrots in the garden

More from Merriam-Webster on thin

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

More from Merriam-Webster