Glamorous girl's city rate (5)
I believe the answer is:
nymph
'glamorous girl's' is the definition.
(beautiful spirit in Greek myth)
'city rate' is the wordplay.
'city' becomes 'NY' (short for New York).
'rate' becomes 'mph' (miles per hour).
'ny'+'mph'='NYMPH'
(Other definitions for nymph that I've seen before include "Dragonfly larva" , "Semi-divine maiden associated with sea or wood" , "Mythological spirit - larva" , "Young dragonfly" , "Female spirit; immature form of dragonfly" .)