cyst

1 of 3

noun

1
: a closed sac having a distinct membrane and developing abnormally in a cavity or structure of the body
2
: a body resembling a cyst: such as
a
: a resting spore of many algae
b
: the air bladder of certain algae or aquatic plants (such as rockweed)
c
: a capsule formed about a minute organism going into a resting or spore stage
also : this capsule with its contents
d
: a resistant cover about a parasite produced by the parasite or the host

cyst-

2 of 3

combining form

variants or cysti- or cysto-
: bladder
cystitis
: sac
cystocarp

-cyst

3 of 3

noun combining form

: bladder : sac
blastocyst

Examples of cyst in a Sentence

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.
Noun
Between 3 percent and 9 percent of people develop voice disorders due to cysts, growths, or cancers that require surgical removal. Aamir Khollam, Interesting Engineering, 29 Oct. 2025 The location and size of a cyst can also dictate whether it should be removed surgically. Jocelyn Solis-Moreira, Flow Space, 27 Oct. 2025 It is characterized by irregular menstrual cycles, excess androgen (male hormone) levels, and polycystic ovaries, which are enlarged ovaries containing numerous small cysts. Memorialcare Medical Group, Oc Register, 23 Oct. 2025 Storms previously underwent a craniotomy in 2021 for the removal of noncancerous cysts from her brain. J. Kim Murphy, Variety, 14 Oct. 2025 See All Example Sentences for cyst

Word History

Etymology

Noun

New Latin cystis, from Greek kystis bladder, pouch; akin to Sanskrit śvasiti he blows, snorts — more at wheeze

Combining form

French, from Greek kyst-, kysto-, from kystis

Noun combining form

New Latin -cystis, from Greek kystis

First Known Use

Noun

circa 1723, in the meaning defined at sense 1

Time Traveler
The first known use of cyst was circa 1723

Browse Nearby Words

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Cite this Entry

“Cyst.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cyst. Accessed 1 Nov. 2025.

Kids Definition

cyst

noun
1
: a closed pouch or sac of fluid or solid material that develops in the body in some diseased conditions
2
: a covering resembling a cyst or a body (as a spore) with such a covering
cystic
ˈsis-tik
adjective

Medical Definition

cyst

noun
1
: a closed sac having a distinct membrane and developing abnormally in a body cavity or structure
2
: a body resembling a cyst: as
a
: a capsule formed about a minute organism going into a resting or spore stage
also : this capsule with its contents
b
: a resistant cover about a parasite produced by the parasite or the host compare hydatid sense 2a

More from Merriam-Webster on cyst

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