Rough verse being penned in 'A Representation of Serbia' (8)
I believe the answer is:
abrasive
'rough' is the definition.
(similar in meaning)
'verse being penned in a representation of serbia' is the wordplay.
'verse' becomes 'v'.
'being penned in' is an insertion indicator.
'representation of' indicates anagramming the letters (I've seen this in other clues).
'serbia' anagrammed gives '[serbia]'.
'a'+'[serbia]'='a[serbia]'
'v' going within 'abrasie' is 'ABRASIVE'.
(Other definitions for abrasive that I've seen before include "Wearing" , "harsh, rough in manner" , "Harsh or insensitive in manner" , "Rough, irritating" , "Emery paper or steel wool, say" .)