(Λάσος), one of the principal Greek lyric poets, was a native of Hermione, in Argolis, and the son of Chabrinus or (according to Schneidewin's emendation) Charminus. He is celebrated as the founder of the Athenian school of dithyrambic poetry, and as the teacher of Pindar. He was contemporary with Simonides (Aristoph. Wasps 1410, and Schol.), like whom, and other great poets of the time, he lived at Athens, under the patronage of Hipparchus. Herodotus mentions his detection of Onomacritus in a forgery of oracles under the name of Musaeus, in consequence of which Hipparchus expelled Onomacritus from Athens (7.6). There also appears to have been a strong rivalry between Lasus and Simonides. (Aristoph. l.c. ; Schol. ad loc. ; Dindorf, Annot. ad Schol.) The time when he instructed Pindar in lyric poetry must have been about B. C. 506 (Thom. Mag. Vit. Pind.); and it must be to this date that Suidas refers, when he places Lasus in the time of Dareius, the son of Hystaspes. (Suid. s. v. where, accordingly, νή should be corrected into ξή.) Nothing further is known of his life, and the notices of his poetry are very defective. Tzetzes mentions him after Arion, as the second great dithyrambic poet. (Proleg. in Lycoph. p. 252, ed. Müller; comp. Schol. ad Pind. Ol. 13.25.) According to a scholiast on Aristophanes (Aristoph. Birds 1403), some ancient writers ascribed to him, instead of Arion, the invention of the cyclic choruses. (Comp. Suid. s. v. κυκλιοδιδάσκαλος.) A better account is given by another scholiast (Vesp. 1410) and Suidas (s. v. Δᾶσος), that Lasus was the first who introduced dithyrambic contests, like those of the dramatic choruses. This seems to have been in Ol. 68, 1, B. C. 508. (Marm. Par. Ep. 46.) Putarch states (De Mus. p. 1141b. c.) that Lasus invented various new adaptations of music to dithyrambic poetry, giving it an accompaniment of several flutes, and using more numerous and more varied voices (or musical sounds, φθόγγοις). The change of form was naturally accompanied by a change in the subjects of the dithyramb. Suidas (s. v.) and the scholiast on Aristophanes (Aristoph. Wasps 1410) tell us that Lasus introduced ἐριστικοὺς λόγους. From these statements, compared with what we know of the earlier dithyramb on the one hand, and on the other with the works of Lasus's great pupil, Pindar, we may infer that Lasus introduced a greater freedom, both of rhythm and of music, into the dithyrambic Ode; that he gave it a more artificial and more mimetic character; and that the subjects of his poetry embraced a far wider range than had been customary. It is difficult, however, to say what the scholiast means by ἐριστικοὺς λόγους. Some writers explain them as jocose altercations among the Satyrs, who formed the chorus; but this is scarcely consistent with the dignity of dithyrambic poetry. Another explanation is that Lasus, like the dramatic poets, introduced into his poetry subjects which afforded occasion for the display of dialectic skill. It is something in confirmation of this view, that, according to some accounts, he was reckoned among the seven wise men of Greece. (Schol. ad Aristoph. Vesp. 1410; Suid. s.v. D. L. 1.42; comp. the note of Menagius. )

Lasus wrote a hymn to Demeter, who was worshipped at Hermione, in the Doric dialect, with the Aeolic harmony, of which there are three lines extant (Ath. xiv. p. 624e.), and an ode, entitled , both of which pieces were remarkable for not containing the letter Σ. (Ath. x. p. 455d.) He is also cited twice by Aelian (V. II. 12.36; N. A. 7.47 ).

Besides his poems, Lasus wrote on music, and he is said to have been the first who did so. (Suid. s. v.)

The grammarian, Chamaeleon of Heracleia, wrote a work upon Lasus. (Ath. viii. p. 338b.)

His name is sometimes mis-spelt by the ancient writers. Tzetzes (Proleg. in Lycophr. l.c.) calls him Δάσσος, and Stobaeus (Serm. xxvii) writes Τάσσος. (Burette, Mém. de l'Acad. des Inscr. tom, xv. p. 324; Forkel, Geschichte d. Musik. vol. i. p. 358; Fabric. Bibl. Graec. vol. ii. p. 128; Böckh, de Metr. Pind. p. 2; Müller, Hist. of the Lit. of Greece, pp. 214, 215; Bode, Geschichte d. lyrischen Dichtkunst. pass.; Ulrici, Gesch. d. Hellen. Dichtk. vol. ii. pass.; Schneidewin, Comment. de Laso Hermionensi, Gotting. 1842.)