Domed roof (6)
I believe the answer is:
cupola
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">domed roof</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>
(Other definitions for cupola that I've seen before include "Dome - furnace" , "St Peter's roof" , "Small dome on a roof" , "Domed ceiling" , "fireplace" .)