From BiblePortal Wikipedia

Fausset's Bible Dictionary [1]

 Genesis 10:2. Josephus (Ant. 1:6, section 1) identifies his descendants with the Thracians, including the Getae (from whence came the Goths) and Dacians. Tuch derives the Tyrsenians from Tiras. (See Rosh .) Thracian tribes occupied most of northern and central Asia Minor originally. The Bithynians were Thracians. So also the Mariandynians, Paphlagonians, Phrygians (another form of the Thracian Briges), and Mysians (answering to the Moesi). Tiras follows Meshech in the genealogy, just as the Thracian tribes of Asia Minor adjoined the Moschi toward the W. Thus Genesis 10 includes among Japhet's descendants the vast nation of the Thracians, extending from the Halys in Asia Minor to the Drave and Save in Europe. Bria (perhaps "town"), in Mesembria, Selymbria, is a solitary relic of the Thracian tongue. The name has been identified as appearing in Aga-thyrsi. Taur-us, and Tyras (the river Dniester).

Hastings' Dictionary of the Bible [2]

TIRAS . A son of Japheth (  Genesis 10:2 ), formerly identified with Thrace , but of late much more plausibly with the Turusha , a piratical people who invaded Syria and Egypt in the 13th cent. b.c. But Tiras has also been identified with Tarsus (= E. Cilicia) and even Tarshish (wh. see).

J. F. McCurdy.

Morrish Bible Dictionary [3]

Son of Japheth: his descendants have not been traced, but are supposed to correspond with the Thracians.  Genesis 10:2;  1 Chronicles 1:5 .

American Tract Society Bible Dictionary [4]

A son of Japeth, supposed to have been the forefather of the ancient Thracians,  Genesis 10:2 .

Holman Bible Dictionary [5]

 Genesis 10:2 1 Chronicles 1:5

Easton's Bible Dictionary [6]

 Genesis 10:2 1 Chronicles 1:5

Cyclopedia of Biblical, Theological and Ecclesiastical Literature [7]

(Heb. Tiras', תַּיֹרָס , Sept. Θείρας ;Vulg. Thisras ) , the youngest son of Japheth (Genesis 10, 2). B.C. 2514. As the name occurs only in the ethnological table, we have no clue, so far as the Bible is concerned, to guide us as to the identification of it with any particular people. Ancient authorities generally fixed on the Thracians, as presenting the closest verbal approximation to the name (Josephus, Ant. 1, 6, 1; Jerome, In  Genesis 10:2; Targums Pseudo-Jon. and Jerus On Genesis loc. cit.; Targ. on  1 Chronicles 1:5); the occasional rendering Persia probably originated in a corruption of the original text. The correspondence between Thrace and Tiras is not so complete as to be convincing; the gentile form Θρᾶξ , however, brings them nearer together. No objection arises on ethnological grounds to placing the Thracians among the Japhetic races (Bochart, Phaleg, 3, 2; Michaelis, Spicileg. 1, 55 sq.). Their precise ethnic position is, indeed, involved in great uncertainty; but all authorities agree in their general Indo European character. The evidence of this is circumstantial rather than direct. The language has disappeared, with the exception of the ancient names and the single word Bria, which forms the termination of Mesembria, Selymbria, etc., and is said to signify "town" (Strabo, 7:319).

The Thracian stock was represented in later times by the Getae, and these, again, still later, by the Daci, each of whom inherited the old Thracian tongue (ibid. 303). But this circumstance throws little light on the subject; for the Dacian language has also disappeared, though fragments of its vocabulary may possibly exist either in Wallachian dialects or perhaps in the Albanian language (Diefenbach, Or. Eur. p. 68). If Grimm's identification of the Getae with the Goths were established, the Teutonic affinities of the Thracians would be placed beyond question (Gesch. d. deutsch. Spr. 1, 178); but this view does hot meet with general acceptance. The Thracians are associated in ancient history with the Pelasgians (Strabo, 9:401), and the Trojans, with whom they had many names in common (ibid. 13:590); in Asia Minor they were represented by the Bithnians (Herod. 1, 28; 7:75). These circumstances lead to the conclusion that they belonged to the Indo-European family, but do not warrant us in assigning them to any particular branch of it. Other explanations have been offered of the name Tiras, of which we may notice the Agathyyrsi, the first part of the name (Aga) being treated as a prefix (Knobel, V Ö lkertafel, p. 129); Taurus and the various tribes occupying that range (Kalisch, Comm. p. 246); the river. Tyras (Dniester), with its cogominous inhabitants the Tyritf (Havernick, Einleit. 2, 231; Schulthess, Prad. p. 194); and, lastly, the maritime Tyrrheni (Tuch, in Genesis loc. cit.). (See Ethnography).

International Standard Bible Encyclopedia [8]

tı̄´ras ( תּירס , tı̄raṣ  ; Θειράς , Theirás , Lucian Θιράς , Thirás ): A son of Japheth (  Genesis 10:2 (P);   1 Chronicles 1:5 ). Not mentioned elsewhere; this name was almost unanimously taken by the ancient commentators (so Josephus, Ant. , I, vi, 1) to be the same as that of the Thracians (Θρᾶκες , Thrákes ); but the removal of the nominative ending ρ Ο2 ςπ does away with this surface resemblance. Tuch was the first to suggest the Τυρσηνιοί , Tursēnioi , a race of Pelasgian pirates, who left many traces of their ancient power in the islands and coasts of the Aegean, and who were doubtless identical with the Etruscans of Italy. This brilliant suggestion has since been confirmed by the discovery of the name Turusa among the seafaring peoples who invaded Egypt in the reign of Merenptah (W.M. Muller, AE , 356 ff). Tiras has also been regarded as the same as Tarshish.