Origin: 1300–50; Middle English armerie, armur(i)e < Middle French armoierie, equivalent to Old French armoi(er) to bear arms (derivative of armesarm2) + -erie-ery
"place where arms are manufactured," 1841, Amer.Eng., from arm (2). Earlier, "arsenal" (1530s) and "the science of heraldry" (late 15c.), from O.Fr. armoierie, from armoier "to blazon," from L. arma "weapons."