'Peristome' definitions:

Definition of 'peristome'

(from WordNet)
noun
(botany) fringe of toothlike appendages surrounding the mouth of a moss capsule
noun
Region around the mouth in various invertebrates

Definition of 'Peristome'

From: GCIDE
  • Peristome \Per"i*stome\ (p[-e]r"[i^]*st[=o]m), n. [Pref. peri- + Gr. sto`ma, sto`matos, mouth.]
  • 1. (Bot.) The fringe of teeth around the orifice of the capsule of mosses. It consists of 4, 8, 16, 32, or 64 teeth, and may be either single or double. [1913 Webster]
  • 2. (Zool.) (a) The lip, or edge of the aperture, of a spiral shell. (b) The membrane surrounding the mouth of an invertebrate animal. [1913 Webster]