deflagration
Concise Oxford English Dictionary © 2008 Oxford University Press:
deflagration/-ˈreɪʃ(ə)n/
▶noun Chemistry the action of heating a substance until it burns away rapidly.
– derivatives
deflagrate verb,
deflagrator noun.
deflagrate verb,
deflagrator noun.
– origin C17: from L. deflagratio(n-), from deflagrare ‘burn up’, from de- ‘away, thoroughly’ + flagrare ‘to burn’.
'deflagration' also found in these Oxford entries:

