peristome
noun
peri·stome
ˈper-ə-ˌstōm 
1
: the fringe of teeth surrounding the orifice of a moss capsule
2
: the region around the mouth in various invertebrates
Examples of peristome in a Sentence
Recent Examples on the Web
Only when wet, the peristome surface is slippery for insects, so that most ant visitors become trapped.
—
Ncbi Rofl, Discover Magazine, 20 Feb. 2013
With the peristome teeth extended, the capsule is only about 1 millimeter wide, yet from afar the mosses often give a drab blackish impression.
—Cecilia Rodriguez, Forbes, 5 Feb. 2023
With the peristome teeth extended, the capsule is only about one millimeter wide, yet from afar the mosses often give a drab blackish impression.
—Alan Taylor, The Atlantic, 9 Jan. 2023
Under the microscope, the secret to the peristome’s slipperiness is clear.
—Ed Yong, Discover Magazine, 21 Sep. 2011
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Ncbi Rofl, Discover Magazine, 20 Feb. 2013
With the peristome teeth extended, the capsule is only about 1 millimeter wide, yet from afar the mosses often give a drab blackish impression.
—Cecilia Rodriguez, Forbes, 5 Feb. 2023
With the peristome teeth extended, the capsule is only about one millimeter wide, yet from afar the mosses often give a drab blackish impression.
—Alan Taylor, The Atlantic, 9 Jan. 2023
Under the microscope, the secret to the peristome’s slipperiness is clear.
—Ed Yong, Discover Magazine, 21 Sep. 2011
Cite this Entry
“Peristome.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/peristome. Accessed 18 Jul. 2025.
Copy CitationMedical Definition
peristome
noun
peri·stome
ˈper-ə-ˌstōm
: the area surrounding the mouth or cytostome of a protozoan
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