The definition of a bonus is anything given beyond the required amount.(noun)
See bonus in Webster's New World College Dictionary
noun pl. bonuses
Origin: L, good < OL dvonus < IE *du-, var. of base *deu-, to venerate > OE (lang)twidig, (long) granted, L beare, pp. beatus, to make happy
See bonus in American Heritage Dictionary 4
noun pl. bo·nus·es
Origin: From Latin, good; see deu-2 in Indo-European roots.
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