Synonyms for Combustible (same or very similar meaning)
WordNet sense 1 (a substance that can be burned to provide heat or power):
combustible material
WordNet sense 2 (capable of catching fire spontaneously or causing fires or burning readily):
incendiary
WordNet sense 3 (easily ignited):
inflammable
WordNet sense 4 (capable of burning):
burnable
From the ODE community, based on WordNet
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