Crossing empty zone with supporter (5)
I believe the answer is:
zebra
'crossing' is the definition.
(zebra crossing is a kind of crossing)
'empty zone with supporter' is the wordplay.
'empty' means to remove the middle letters.
'with' is a charade indicator (letters next to each other).
'supporter' becomes 'bra' (I've seen this before).
'zone' with its centre taken out is 'ze'.
'ze'+'bra'='ZEBRA'
(Other definitions for zebra that I've seen before include "African mammal" , "African beast" , "Braze (anag.)" , "that's stripy" , "Striped quadruped" .)