This girl’s relative edges round Iowa (5)
I believe the answer is:
sonia
'this girl's' is the definition.
(woman's name)
'relative edges round iowa' is the wordplay.
'relative' becomes 'son' (son is a kind of relative).
'edges round' suggests removing the centre (only the edge letters remain).
'iowa' with its middle removed is 'ia'.
'son'+'ia'='SONIA'
(Other definitions for sonia that I've seen before include "...O'Sullivan, great Irish athlete" , "Noa is really a girl" .)