ärˈbāsēə noun
Etymology: New Latin, from Arbaces died ab 848 B.C. king of Media + New Latin -ia
1. capitalized : a genus of sea urchins (order Centrechinoida) having the ambulacral plates with three pairs of pores, the periproct covered by four triangular plates, the test rather low and stout, and the spines short with those near the mouth having enameled flattened tips
2. -s : a sea urchin of the genus Arbacia