Smooth covering for walls and ceilings (7)
I believe the answer is:
plaster
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">smooth covering for walls and ceilings</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for plaster that I've seen before include "Smear" , "Adhesive dressing" , "First-aid item" , "Stuff that sticks on ceilings or wounds" , "Adhesive material" .)