D defs.my
Entry 1 sense Webster, 1913

Bonanza

/bən-ăn'-zə/ · Bo·nan·za · IPA /bəˈnæn.zə/
01 n. In mining, a rich mine or vein of silver or gold; hence, anything which is a mine of wealth or yields a large income.
  1. 1.
    In mining, a rich mine or vein of silver or gold; hence, anything which is a mine of wealth or yields a large income.[Colloq. U. S.]