Lewis & Short

ăpĭastrum, i, n. [apis].

  1. I. Wild-parsley: Selinum palustre, Linn.; Plin. 21, 12, 41, § 70; cf. Col. 9, 8, 12.
  2. II. Balm, a plant of which bees are fond: melissophyllon, Varr. R. R. 3, 16, 10; Plin. 21, 9, 29, § 53.