Lewis & Short

Telmessus, Telmissus, or Tel-mēsus, i, f., = Τελμησσος or Τελμισσός, a town in Lycia, near to Caria, at the head of the Glaucus Sinus, now Makri; it was famed for the skill of its inhabitants in divination, Cic. Div. 1, 41, 91; Mel. 1, 15, 3; Plin. 30, 1, 2, § 6; Liv. 38, 39.
Hence,

  1. A. Telmessĭcus (Telmissĭcus, -mē-sicus), a, um, adj., of or belonging to Telmessus, Telmessian: Telmissicus sinus, Liv. 37, 16 Telmessicum vinum, Plin. 14, 7, 9, § 74.
  2. B. Telmissĭus, a, um, adj., of Telmissus, Telmissian. Ptolemaeus, Liv. 37, 56, 4.
    As subst. Telmissĭi, ōrum, m., the innabitants of Telmissus, the Telmissians: Castra Telmissium, Liv. 37, 56 Drak. N. cr. (s. l. v.).
  3. C. Telmesses (-me-ses), ĭum, m., Cic. Div 1, 42, 94; or Tel-messenses, ĭum, m., the inhabitants of Telmessus, the Telmessians, Tert. Anim. 46.
  4. D. Telmessis, ĭdis, adj. f., Telmessian: sinus, Luc. 8, 248.