Drink additive (3,4)
(Other definitions for ice cube that I've seen before include "Cooling addition to drink" , "Drink cooler" , "Frozen shape in a drink" , "Six-faced frozen cooler" , "Block used in cold drinks" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">drink additive?</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Another definition for ade that I've seen is " -- Edmondson, comedian".)