A determinate quantity or
magnitude of the kind designated, taken as a standard of comparison for others
of
the same kind, in assigning to them numerical values, as 1 foot, 1 yard,
1 mile, 1
square foot, 1 square yard, 1 cubic foot, 1 peck, 1 bushel, 1 gallon, 1 cent,
1
ounce, 1 pound, 1 hour, and the like.