Lewis & Short

Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Perseus.

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.

Nāĭs, idis and ĭdos, v. Naias.