[1] : The Collaborative International Dictionary of English v.0.48

combust \combust"\, a. l. combustus, p. p. of comburere to
   burn up; com- + burere only in comp., of uncertain origin;
   cf. bustum funeral pyre, prurire to itch, pruna a live coal,
   gr. pyrso`s firebrand, skr. plush to burn.
   1. burnt; consumed. obs. --chaucer.
      1913 webster

   2. astron. so near the sun as to be obscured or eclipsed by
      his light, as the moon or planets when not more than eight
      degrees and a half from the sun. obs.
      1913 webster

            planets that are oft combust.         --milton.
      1913 webster

[2] : WordNet (r) 2.0

combust
     v 1: cause to burn or combust; "the sun burned off the fog"; "we
          combust coal and other fossil fuels" syn: burn
     2: start to burn or burst into flames; "marsh gases ignited
        suddenly"; "the oily rags combusted spontaneously" syn: erupt,
         ignite, catch fire, take fire, conflagrate
     3: get very angry and fly into a rage; "the professor combusted
        when the student didn't know the answer to a very
        elementary question"; "spam makes me go ballistic" syn: flip
        one's lid, blow up, throw a fit, hit the roof, hit
        the ceiling, have kittens, have a fit, blow one's
        stack, fly off the handle, flip one's wig, lose
        one's temper, blow a fuse, go ballistic
     4: cause to become violent or angry; "riots combusted pakistan
        after the u.s. air attacks on afghanistan"
     5: undergo combustion; "maple wood burns well" syn: burn
see also:
burn erupt ignite catch fire take fire conflagrate 
flip one's lid blow up throw a fit hit the roof hit the ceiling 
have kittens have a fit blow one's stack fly off the handle flip one's wig 
lose one's temper blow a fuse go ballistic 

Combust >> C Words
Combust, definition of term: Combust
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