. "opercular opening" . "Opercula" . . "opercular plates" . "operculums" . "operculi" . "opercula" . "operculum (gastropod)" . "operculum" . "operculate" . "Operculum (gastropod)" . "Operculum" . . . "Operculum (gastropod)" . . "deck" . "opercular" . "Operculum (gastropod)#Use as incense material" . . . "operculate snail" . . "Operculum (gastropod)#Use as a gem - Shiva's eye" . . "operculated" . . . .