Girl going about sporting such a flower (7)
I believe the answer is:
fuchsia
'flower' is the definition.
(I've seen this before)
'girl going about sporting such a' is the wordplay.
'girl' becomes 'fi' (nickname for Fiona).
'going about' means one lot of letters goes inside another.
'sporting' is an anagram indicator.
'such' is an anagram of 'uchs'.
'fi' enclosing 'uchs' is 'fuchsi'.
'fuchsi'+'a'='FUCHSIA'
(Other definitions for fuchsia that I've seen before include "One blooming" , "Pendulous-flowered shrub" , "Flowering shrub" , "Flower; colour" , "If such a thing could be a wild flower" .)