Operculum

Operculum may refer to:

In human biology:

• Operculum (in pregnancy), the cervical mucus plug that blocks the cervix of the uterus after conception
• Operculum (brain), the part of the brain covering the insula
• Operculum (dentistry), a small flap of tissue which may cover an erupting or partially erupted molar

In animal biology:

• Operculum (animal), a structure resembling a lid or a small door that opens and closes
  • Operculum (fish), a flap of the bony fish covering the gills
  • Operculum (gastropod), a lid on the shell of some gastropods
  • Operculum (bird), a structure which covers the nares of some birds
  • Operculum (bryozoa), a lid on the orifice of some bryozoans

In botany:

• Operculum (botany), various lids and flaps pertaining to plants, algae and fungi