gram (n.) Look up gram at
also gramme, metric unit of weight," 1797, from French gramme (18c.), from Late Latin gramma "small weight," from Greek gramma "small weight," originally "letter of the alphabet," from stem of graphein "to draw, write" (see -graphy). Adopted into English about two years before it was established in France as a unit in the metric system by law of 19 frimaire, year VIII (1799). "There seems to be no possible objection to adopting the more convenient shorter form, except that the -me records the unimportant fact that the word came to us through French" [Fowler].