Lewis & Short

Nāĭăs, ădis, and more freq. Nāĭs, ĭdis and ĭdos (plur. ĭdas), f., = Ναϊάς and Ναἱς (floating, swimming, that is in the water),

  1. I. a water-nymph, Naiad: illum fontana petebant Numina, Naïades, Ov. M. 14, 328: Aegle Naïadum pulcherrima, Verg. E. 6, 21: Naïs Amalthēa, Ov. F. 5, 115.
    Poet. of mixing wine with water: Naïda Bacchus amat, Tib. 3, 6, 57.
    Adj.: puellae Naïdes, Verg. E. 10, 10.
  2. II. Transf., in gen., a nymph (Hamadryad, Nereid): Naïda vulneribus succidit in arbore factis, Ov. F. 4, 231: inter Hamadryadas celeberrima Naias, id. M. 1, 691: Naïdes aequoreae, id. ib. 14, 557.
  3. III. The surname probably of a freedwoman: Servilia Naïs, Suet. Ner. 3.
    Hence, Nāĭcus, a, um, adj., of the Naids, proceeding from the Naids: dona, Prop. 2, 32, 40.
    1. B. As subst.: Nāĭcus, i, m., a Roman surname, Inscr. Grut. 241, col. 2.
      In fem.: ‡ Nāĭcē, Inscr. Fabr. p. 650, n. 433.