πτύξ

ῆς, ἡ
A. πτυχί Il. 20.22: pl. πτύχες, πτύχας, 7.247, al., Hes. Sc. 143, etc.: after Hom. πτυχή, ῆς, which prevails in Pi. (v. infr. 11) and Trag.; the metre requires acc. sg. πτύχα in E. Supp. 979 (lyr.), but acc. pl. πτυχάς in S. Fr. 144; in other places either πτύχας or πτυχάς will suit the metre:—poet. word, layer, plate, mostly in pl., σάκεος πτύχες plates of metal or leather, in strong shields, Il. 18.481, cf. 7.247, 20.269, Hes. Sc. 143.
2. fold (i.e.folded piece) of a garment, in pl., first in h.Cer. 176, then in S. Fr. 494, E. Supp. 979 (lyr.); of the entrails, κατὰ σπλάγχνων πτυχάς ib.212; εἰς τὰς πτυχάς Arist. HA 549a17; coats of the stomach, Gal. 2.556; layers of muscles, Id. 18(2).944.
3. writing tablets, ἐν πτυχαῖς βίβλων κατεσφραγισμένα A. Supp. 947; γραμμάτων πτυχὰς ἔχων S. Fr. 144; ἐν δέλτου πτυχαῖς E. IA 98, cf. IG 9 (1).880.10 (Corc.).
II. in hilly country, folds, glens, κατὰ πτύχας Οὐλύμποιο Il. 11.77; πτύχες ἠνεμόεσσαι (from the wind that rushes down narrow mountain-clefts), Od. 19.432; also in sg., πτυχὶ Οὐλύμποιο, Παρνησοῖο, Il. 20.22, h.Ap. 269, h.Merc. 555; πτυχαὶ Κρισαῖαι, Πίνδου, Πέλοπος, Pi. P. 6.18,9.15, N. 2.21; ἐν Κιθαιρῶνος πτυχαῖς S. OT 1026, cf. E. Supp. 757, Ba. 62, Andr. 1277; Αὐλίδος κατὰ πτυχάς Id. IT 1082, cf. 9: also of the sky, πτυχαὶ αἰθέρος, οὐρανοῦ, Id. Or. 1631, Hel. 44, Ph. 84: sg., μέχρις οὐρανοῦ πτυχός Ezek. Exag. 69.
III. metaph., ὕμνων πτυχαί folds of song, i.e. sinuous songs, Pi. O. 1.105.
IV. acc. pl. πτυχάς or πτύχας leaves of a folding door, metaph., ὁ κλείσας οὐρανοῦ δισσὰς π. PMag.Par. 1.190; nom. πτύχες, = θύραι, σανίδες, Poll. 10.24.
V. πτυχή,ἡ, the part of a ship on which her name was inscribed, A.R. 1.1089; cf. πτυχίς.
Liddell, Scott & Jones
A Greek-English Lexicon, 1940
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