pennyweight

A unit of troy weight equal to 24 grains, ¹/₂₀ of a troy ounce or about 1.555 grams.

Originally, a weight equal to that of the Anglo-Norman silver penny, 22 ½ grains, or of a Tower pound; now, and since the eighteenth year of Henry VIII., when the use of the Tower pound was forbidden, a weight of 24 grains, or of a troy ounce. Abbreviated dwt.

A proportional measure of one-twelfth, used in stating the fineness of silver. See carat.

A troy weight containing twenty-four grains, or the twentieth part of a troy ounce; 1.555 grams. It is abbreviated dwt or pwt. It was anciently the weight of a silver penny, whence the name.

A former unit of mass equal to 24 grains, or 1/20th of a troy ounce

a unit of apothecary weight equal to 24 grains