echinus
/ɪˈkʌɪnəs
/noun
1 Zoology A sea urchin.
- Genus Echinus, class Echinoidea: several species.
2 Architecture A rounded moulding below an abacus on a Doric or Ionic capital.
Origin
Late Middle English: via Latin from Greek ekhinos 'hedgehog, sea urchin'.