Solid block (4)
(Other definitions for cube that I've seen before include "Square-sided body" , "Square block" , "Form of chiller" , "Lump of sugar" , "Square-faced solid" .)
(Other definitions for ice that I've seen before include "Constituent of 2dn" , "Finish decorating the Christmas cake" , "Precious stones" , "Diamonds (sl)" , "To put in a drink or slide on" .)