Capitol rebuilt in sight (7)
I believe the answer is:
optical
'in sight' is the definition.
(optical means relating to sight)
'capitol rebuilt' is the wordplay.
'rebuilt' indicates an anagram.
'capitol' with letters rearranged gives 'OPTICAL'.
(Other definitions for optical that I've seen before include "Involving light" , "Concerning sight" , "Using visible light" , "Visual" , "Concerning light" .)