The Collaborative International Dictionary
Perichaeth
Perichaeth \Per"i*ch[ae]th\, n. [See Perich[ae]tium.] (Bot.) The leafy involucre surrounding the fruit stalk of mosses; perich[ae]tium; perichete.
Wiktionary
perichaeth
n. (context botany English) The leafy involucre surrounding the fruit stalk of mosses; perichaetium; perichete.