#sea_nymph__seanymph  (Greek mythology) a water nymph who was the daughter of Oceanus or Nereus
  supertype:  water_nymph__waternymph  (Greek mythology) any nymph of the water
  instance:  Calypso  Oceanid
  subtype:  Nereid  (Greek mythology) any of the 50 sea nymphs who were daughters of the sea god Nereus
     instance:  Thetis
  subtype:  Siren  a sea nymph (part woman and part bird) supposed to lure sailors to destruction on the rocks where the nymphs lived; "Odysseus ordered his crew to plug their ears so they would not hear the Siren's fatal song"
     subtype:  Lorelei  a siren of German legend who lured boatmen in the Rhine to destruction

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