What is to cause to burn with sudden and sparkling combustion, as by the action of intense heat; to burn or vaporize suddenly; as, to deflagrate refractory metals in the oxyhydrogen flame called?

deflagrate — To cause to burn with sudden and sparkling combustion, as by the action of intense heat; to burn or vaporize suddenly; as, to deflagrate refractory metals in the oxyhydrogen flame. (Webster's 1913.)

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