Remains of a fire (5)
(Other definitions for ashes that I've seen before include "Remains from a cremation" , "sporting trophy" , "Remains of anything burnt" , "Eng./Aus. cricket trophy" , "Former Wimbledon champion's" .)
'remains of a fire' is the definition.
(I've seen this before)
This is all the clue.
(Other definitions for ash that I've seen before include "Tree; burnt residue" , "Hard pale wood" , "Burnt remains; tree" , "Volcanic dust" , "Timber tree" .)