Lewis & Short

1. stagnum, i, n. [cf. Gr. τέναγος = vadum].

  1. I. Lit., a piece of standing water (whether permanent or formed by the overflowing of a stream], a pool, pond, swamp, fen, etc. (cf.: lacus, palus): propter stagna, ubi lanigerum pecus piscibus pascit, Enn. ap. Paul. ex Fest. p. 59 Müll. (Sat. v. 42 Vahl.): super ripas Tiberis effusus lenibus stagnis, Liv. 1, 4, 4; cf. Varr. ap. Non. 217, 2 (as an example for stativae aquae); Cic. poët. Div. 1, 9; Auct. ap. Cic. Agr. 3, 2, 7; Tib. 1, 3, 77; Verg. A. 6, 323: undique latius Extenta Lucrino Stagna lacu, Hor. C. 2, 15, 4: immensa stagna lacusque, Ov. M. 1, 38; Liv. 26, 48, 4 al.
  2. II. Poet., transf., waters in gen.: hiemem sensit Neptunus et imis Stagna refusa vadis. Verg. A. 1, 126: Nerei Stagna, id. ib. 10, 764: rubri stagna profundi, Luc. 8, 853; cf. Sil. 7, 282: stagna tepentis aquae, Prop. 3, 18 (4, 17), 2: Phrixeae stagna sororis, i. e. the Hellespont, Ov. F. 4, 278: Euripi, id. P. 1, 8, 38: stagnum ignis, a lake of fire, Vulg. Apoc. 19, 20; 20, 10.