Lewis & Short

subter (also supter), adv. and prep. [sub].

  1. I. Adv., below, beneath, underneath: navem in fugam transdunt subter saxa, Att. ap. Non. 155, 8 (Trag. Rel. v. 630 Rib.): terram fac ut esse rearis Subter item, ut supera, Lucr. 6, 537: partim quod supter per terras diditur omnis, id. 5, 268: aliam naturam supter habere, id. 5, 536: omnia haec, quae supra et subter, unum esse, Cic. de Or. 3, 5, 20; id. poët. N. D. 2, 42, 106: anulus subter adhaerens, Lucr. 6, 914: oculum subter premere, id. 4, 447: subter mediam fere regionem sol obtinet, Cic. Rep. 6, 17, 17.
    Comp.: subterius (opp. superius), Isid. 16, 8, 4.
  2. II. Prep. with acc. and abl., below, beneath, underneath, under (rare but class.).
          1. (α) With acc.: cupiditatem subter praecordia locavit, Cic. Tusc. 1, 10, 20; cf. id. ib. 5, 1, 4: subter pineta, Prop. 2, 34 (3, 32), 67: subter fastigia tecti, Verg. A. 8, 366: agere vias subter mare, id. ib. 3, 695: subter imas cavernas, Ov. M. 5, 502: manu subter togam exserta, Liv. 8, 9: super subterque terram pugnare, id. 39, 4: subter murum hostium ad cohortes advehitur, underneath, i. e. close to the walls, id. 34, 20: latitudo Italiae subter radices (Alpium), Plin. 3, 19, 23, § 132; Stat. Th. 12, 711; Petr. 98.
          2. (β) With abl.: Rhoeteo subter litore, Cat. 65, 7: subter densā testudine, Verg. A. 9, 514.
  3. III. In composition, subter, like sub, denotes underneath, beneath: subteractus, subterfluo, etc.; and also, transf., secretly, privately, clandestinely: subterduco, subterfugio. It is sometimes doubtful whether subter forms a compound with a verb, or is an adverb qualifying it.