Icy rain (4)
(Other definitions for hail that I've seen before include "Ice pellets - greeting" , "Word of greeting" , "Acclaim; frozen rain" , "Call for - praise, vociferously" , "Frozen rain or Roman greeting" .)
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">icy rain</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for sleet that I've seen before include "Partly melted falling snow or hail" , "Rain mixed with snow or hail" , "In foul weather" , "Partly melted falling 16 across or 18 down" , "Mixed rain and melting snow" .)