Who has first of weddings in Reno overturned (5)
I believe the answer is:
owner
'who has' is the definition.
(a person who has things)
'first of weddings in reno overturned' is the wordplay.
'first of' suggests taking the first letters.
'in' indicates putting letters inside.
'overturned' shows that the letters should be reversed in order.
The first letter of 'weddings' is 'w'.
'w' inserted inside 'reno' is 'renwo'.
'renwo' in reverse letter order is 'OWNER'.
(Other definitions for owner that I've seen before include "Title holder?" , "One who possesses" , "landlord" , "One who has something" , "Holder, possessor" .)