Grain, as a unit of weight, is supposed to be the average weight of a seed or well-ripened ear of wheat; of such grains 7000 are held to be a pound avoirdupois. The grain is also the 20th part of a scruple in apothecaries' weight, and the 24th part of a pennyweight troy. See also GRAMME.
Grain
Chambers's Encyclopaedia, Volume 5: Friday to Humanitarians, p. 345
Source scan(s): p. 0356