Hurt, that is, by an attractive girl (5)
I believe the answer is:
cutie
'an attractive girl' is the definition.
(cutie can mean an attractive person)
'hurt that is by' is the wordplay.
'hurt' becomes 'cut' (cut is a kind of hurt).
'that is' becomes 'ie' (short for Latin 'id est', 'that is').
'by' means one lot of letters go next to another.
'cut'+'ie'='CUTIE'
(Other definitions for cutie that I've seen before include "lovely" , "Appealing young lady" , "considered by most to be attractive" , "an attractive thing" , "something pleasing" .)