Copy breaching section of battlement (7)
I believe the answer is:
parapet
'battlement' is the definition.
(thesaurus)
'copy breaching section' is the wordplay.
I cannot quite understand how this works, but
'copy' could be 'ape' (ape can mean to copy or imitate) and 'ape' is found within the answer.
'section' could be 'part' (synonyms) and 'part' is found in the remaining letters.
No letters remain.
This explanation may well be incorrect...
'of' acts as a link.
Can you help me to learn more?
(Other definitions for parapet that I've seen before include "Roof-edge wall" , "form of protection" , "part of castle" , "defensive position" , "Low wall round edge of balcony" .)