exostome

noun
ex·​o·​stome | \ ˈeksəˌstōm \
plural -s

Definition of exostome

1 botany : the opening of the outer integument of an ovule that has two integuments
2 : the outer part of the peristome of a moss

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History and Etymology for exostome

International Scientific Vocabulary exo- + -stome; probably originally formed in French

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Cite this Entry

“Exostome.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/exostome. Accessed 12 Aug. 2020.

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