Source : Webster's Revised Unabridged Dictionary (1913)

Harquebus \Har"que*bus\, Harquebuse \Har"que*buse\, n. [See
   {Arquebus}.]
   A firearm with match holder, trigger, and tumbler, made in
   the second half of the 15th century. the barrel was about
   forty inches long. A form of the harquebus was subsequently
   called arquebus with matchlock.

Source : WordNet®

harquebus
     n : an obsolete firearm with a long barrel [syn: {arquebus}, {hackbut},
          {hagbut}]