Source : Webster's Revised Unabridged Dictionary (1913)

Bonus \Bo"nus\, n.; pl. {Bonuses}. [L. bonus good. Cf. {Bonny}.]
   1. (Law) A premium given for a loan, or for a charter or
      other privilege granted to a company; as the bank paid a
      bonus for its charter. --Bouvier.

   2. An extra dividend to the shareholders of a joint stock
      company, out of accumulated profits.

   3. Money paid in addition to a stated compensation.