Lewis & Short

Lībēthra, ae, f. (or ōrum, n.; Lībē-thros or -us, i, m., Serv. Verg. E. 7, 21), = Λείβηθρα,

  1. I. a fountain near Magnesia, in Macedonia, sacred to the Muses, Mel. 2, 3, 2; Plin. 4, 9, 16, § 32.
    Hence,
  2. II. Lībēthris, ĭdis, f., = Λειβηθρίς, Libethrian: fons, Mart. Cap. 6, § 654.
    Plur. subst.: Lībēthrĭ-dĕs, the Muses: nymphae Libethrides, Verg. E. 7, 21.