Bonfire (4)
I believe the answer is:
pyre
'bonfire' is the definition.
(I have seen 'Ceremonial bonfire ' mean 'pyre' so perhaps 'bonfire' could also mean 'pyre')
This is all the clue.
(Other definitions for pyre that I've seen before include "Heap of combustible material for burning a body" , "Cremation mound" , "Heap of wood for burning a dead body" , "Heap of wood for ritually burning a body" , "Funerary heap" .)