Lewis & Short

Tyndăreus (trisyl.; but quadrisyl. Ov. H. 8, 31; 17, 250), ĕï (Tyndărus, i, Hyg. Fab. 77; 78; Lact. 1, 10, 11), m., = Τυνδάρευς, a king of Sparta, son of Œbalus, and husband of Leda; he was the father of Castor and Pollux, and of Helen and Clytemnestra, Pac. ap. Non. 496, 31; Att. ap. Prisc. p. 1325 P.; Cic. Fat. 15, 34; Ov. H. 8, 31; 17, 250; Hyg. Fab. 77; 78.
Hence,

  1. A. Tyndărĭus, a, um, adj., of or belonging to Tyndareus, Tyndarian: fratres, i. e. Castor and Pollux, Val. Fl. 1, 570: puer, id. 1, 167 (al. Tyndareos as Gr. gen., v. Tyndareus).
    In plur.: Tyndărĭi, ōrum, m., poet. for Spartans, Sil. 15, 320.
  2. B. Tyn-dărĭdes, ae, m., a male descendant of Tyn dareus, i. e. Castor or Pollux; most freq. in plur. for both, Tyndaridae, Cic. de Or. 2, 86, 352; id. Tusc. 1, 12, 28; id. N. D. 2, 2, 6; Ov F. 5, 700; id. M. 8, 301; Hor. C. 4, 8, 31.
    Also for the children of Tyndareus, in gen.: (Clytaemnestra) fortissima Tyndaridarum, Hor. S. 1, 1, 100.
    In sing., of Pollux, Val. Fl. 4, 247; 6, 212.
  3. C. Tyndă-ris, ĭdis, f.
    1. 1. A female descendant of Tyndareus; of Helen, Lucr. 1, 464; 1, 473; Verg. A. 2, 601; 2, 569; Prop. 2, 32 (3, 30), 31; 3, 8 (4, 7), 30; Ov. A. A. 1, 746; id. M. 15, 233. Of Clytemnestra, Ov. Tr. 2, 396; id. A. A. 2, 408.
    2. 2. The name of a town on the north ern coast of Sicily, near the modern Capo Tindaro, Plin. 3, 8, 14, § 90; 2, 92, 94, § 206; Cic. Verr 2, 5, 49, § 128.
      Hence,
      1. b. Tyn-dărĭtāni, ōrum, m., the inhabitants of Tyndaris, Cic. Verr 2, 2, 65, § 156; id. Att 15, 2, 4.
    3. 3. The name of a female friend of Horace, Hor C. 1, 17, 10.