noun ex·o·stome \ˈeksəˌstōm\

Definition of exostome



  1. 1 botany :  the opening of the outer integument of an ovule that has two integuments

  2. 2 :  the outer part of the peristome of a moss

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Origin and Etymology of exostome

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

Seen and Heard

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feeling or affected by lethargy

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