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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
Some surgeons argue that necrosis and cysts may be less of a risk with Alloclae than with a patient’s own fat, since Alloclae doesn’t contain living cells with the potential to die and cause those problems. Jolene Edgar, Allure, 19 Nov. 2025 Celebrity medium Tyler Henry is recovering after undergoing his second surgery in six months to treat a cyst growing on his brain. Glenn Garner, Deadline, 15 Nov. 2025 Tyler's medical team decided that another surgery to address the recurring cyst and swelling was the best option. Mekishana Pierre, Entertainment Weekly, 14 Nov. 2025 After having surgery to remove a cyst growing in his brain in May, the 29-year-old reality TV star required another procedure to address swelling as the cyst recurred, Clint Godwin confirmed in an Instagram post. Anthony Robledo, USA Today, 14 Nov. 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

Cite this Entry

“Cyst.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cyst. Accessed 30 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

Last Updated: - Updated example sentences
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