Source : Webster's Revised Unabridged Dictionary (1913)

Propane \Pro"pane\, n. [Propyl + methane.] (Chem.)
   A heavy gaseous hydrocarbon, {C3H8}, of the paraffin series,
   occurring naturally dissolved in crude petroleum, and also
   made artificially; -- called also {propyl hydride}.

Source : WordNet®

propane
     n : colorless gas found in natural gas and petroleum; used as a
         fuel