Lewis & Short

1. ăcer, ĕris, n. [kindred with Germ. Ahorn] (f. Serv. ap. Prisc. p. 698 P.),

  1. I. the maple-tree, Plin. 16, 15, 26, § 66 sq.
  2. II. Transf., the wood of the maple-tree, maplewood, used, on account of its hardness and firmness, for writing-tablets, Plin. 33, 11, 52, § 146; Ov. Am. 1, 11, 28.