Ounce n.
 1. A unit of mass or weight, the sixteenth part of a pound avoirdupois, and containing 28.35 grams or 437½ grains.
 2. Troy Weight The twelfth part of a troy pound; one troy ounce weighs 31.103486 grams, 8 drams, or 480 grains.
 Note: ☞ The troy ounce contains twenty pennyweights, each of twenty-four grains, or, in all, 480 grains, and is the twelfth part of the troy pound.  The troy ounce is also a weight in apothecaries' weight. [Troy ounce is sometimes written as one word, troyounce.]
 3. Fig.: A small portion; a bit. [Obs.]
    By ounces hung his locks that he had.   --Chaucer.
 Fluid ounce. See under Fluid, n.
 Troy·ounce n. See Troy ounce, under Troy weight, above, and under Ounce.
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