Lewis & Short

lactūca, ae, f. [lac].

  1. I. Lettuce, Plin. 19, 8, 38, § 125 sqq.; Col. 10, 179; 11, 3, 25 sq.; Verg. M. 76; Cels. 2, 32; Mart. 13, 14, 1; several species are described by Plin. H. N. 20, 7, 24, § 58 sqq.
  2. II. Lactuca marina, the plant wolf’s-milk, Cels. 5, 7; Col. 6, 15, 2.