fold, layer; glen
Ancient Greek word, found 20 times in the texts on Socratos.
Euripides, Suppliants 757: τάφῳ δέδονται πρὸς Κιθαιρῶνος πτυχαῖς.
Euripides, Iphigenia in Tauris 9: Ἀρτέμιδι κλειναῖς ἐν πτυχαῖσιν Αὐλίδος.
All forms of πτυχή