n 1  :  a solid having a circular base and sides that slope evenly to a point  2 a  :  any of the conical photosensitive receptor cells of the vertebrate retina that function in color vision - compare ROD   b  :  any of a family (Conidae) of numerous somewhat conical tropical gastropod mollusks that include a few highly poisonous forms - see CONUS   3  :  a cusp of a tooth esp. in the upper jaw .
 
 
 
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