plural noun

: a family of usually large acrocarpous mosses (order Polytrichales) that have simple or branching erect shoots growing from an underground stem, leaves with the costae bearing longitudinal lamellae of variable structure, antheridia borne in conspicious saucer-shaped terminal rosettes, and capsules which are characteristically angular in cross section with a peristome several cells thick see pogonatum , polytrichum

Word History


New Latin, from Polytrichum, type genus + -aceae

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Dictionary Entries Near Polytrichaceae

Cite this Entry

“Polytrichaceae.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/Polytrichaceae. Accessed 21 Jul. 2024.

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