discophora

from The Century Dictionary.

• The discoidal hydrozoans, a subclass of Hydrozoa, comprising most of the organisms known as jelly-fishes, sea-jellies, or sea-nettles.
• An order of suctorial worms, the leeches: so called from their sucking-disks. See Hiru-dinea.

from the GNU version of the Collaborative International Dictionary of English.

• noun plural (Zoöl.) A division of acalephs or jellyfishes, including most of the large disklike species.