D defs.my
Entry 3 senses Webster, 1913

Operculum

· O·per·cu·lum · IPA /oʊˈpɝ.kjə.ləm/
01 n. The lid of a pitcherform leaf.
pl. Opercula, Operculums ((#))
  1. 1.
    The lid of a pitcherform leaf.(Bot.)
  2. 2.
    Any lidlike or operculiform process or part; as, the opercula of a dental follicle.(Anat.)
  3. 3.
    The lid closing the aperture of various species of shells, as the common whelk. See Illust. of Gastropoda.(Zool.) See: Gastropoda