Merriam-Webster Collegiate Dictionary - ounce

 I. noun  Etymology: Middle English, from Anglo-French unce, from Latin uncia 12th part, ~, from unus one — more at one  Date: 14th century  1.  a. a unit of weight equal to 1/12 troy pound — see weight table  b. a unit of weight equal to 1/16 avoirdupois pound  c. a small amount an ~ of sense  2. fluid ~  II. noun  Etymology: Middle English unce lynx, from Middle French, alteration (by misdivision, as if l'once the ~) of lonce, probably from Old Italian lonza, from Middle Greek lynk-, lynx, from Greek  Date: 1774 snow leopard