ἴς

English (LSJ)

(A) [ῑ], ἡ, gen. ἰνός, acc. ἶνα, nom.pl. ἶνες, dat.

   A ἴνεσι Il.23.191, also ἰσίν Sor. (v. infr.), Suid. s.v. ἶνες, cj. Nauck for εἰσίν in A.Fr.229:— sinew, tendon, sg. once in Hom., ὡς δ' ὅτ' ἂν . . ἀνὴρ . . ἶνα τάμῃ διὰ πᾶσαν Il.17.522: usu. in pl., sinews, οὐ γὰρ ἔτι σάρκας τε καὶ ὀστέα ἲνες ἔχουσιν Od.11.219, cf. Il.23.191; ἶνες ἄρθρων Ar.Pax86, cf. Archil.138; ἶνες αὐτὸ μόνον καὶ λεπτὴ δορά, of a person wasted by disease, Ph.2.432; δοράς, σάρκας, ἶνας ib.527: metaph., Τρωίας ἶνας ἐκταμὼν δορί Pi.I.8(7).57.    2 later, the fibrous vessels in the muscles, Pl.Ti.84a, Arist.HA515b27, al.; in blood, fibrine, Id.PA650b14, cf. Pl.Ti.82c, Meno Iatr.17.34: metaph., of metals, Plu.2.434b.    3 rib in the leaves of plants, Thphr.HP3.12.7 (sg.).    4 strip of papyrus, ταῖς τῶν χαρτῶν ἰσίν Sor.1.13: sg., Gal.10.1000.    b λεπτὴ ἴς a small fibre of papyrus, Id.17(1).795.
ἴς (B) [ῑ], ἡ, three times in acc. sg. ἶνα (elided ἶν') Il.5.245,7.269, Od.9.538, freq. in instr. ἶφι (q.v.), elsewh. only nom. sg.:—

   A strength, force, of persons, ἀλλ' ἄρα καὶ ἲς ἐσθλή Il.12.320; ἐπέρεισε δὲ ἶν' ἀπέλεθρον 7.269; ἤ μοι ἔτ' ἐστὶν ἴς, οἵη πάρος . . Od.21.283, cf. 11.393, 18.3: freq. in periphr., ἱερὴ ἲς Τηλεμάχοιο the strong Telemachus, 2.409; κρατερὴ ἲς Ὀδυσῆος Il.23.720; ἲς Ἡρακλῆος Hes.Th.951; and in twofold periphr., ἲς βίης Ἡρακληείης ib.332; also of things, ἲς ἀνέμου or ἀνέμοιο, Il.15.383, 17.739, Od.9.71; ἲς ποταμοῖο Il.21.356; κράται' ἴς was read by Ptol.Asc.in Od.11.597; v. κρατύς. (ϝῑ-, cf. γίς· ἰσχύς, Hsch., pr. n. ϝιφιάδας IG7.3172.70, Lat. vis, vim; prob. cogn. with ἵεμαι but not with ἴς (A).)