Dome (6)
I believe the answer is:
cupola
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">dome</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I know that cupola is a type of dome)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for cupola that I've seen before include "Small dome on a roof" , "St Peter's roof" , "Round domed roof" , "Rounded dome" , "Dome - furnace" .)