1. the lower part of the back, the chine , (Iliad by Homer): then, the spine or backbone , ὑπὸ ῥάχιν παγῆναι to be impaled, (Aeschulus Tragicus) 2. anything ridged like the backbone, a mountain-ridge , (Herdotus Historicus) (ML)
STRONG'S WORD STUDY
G9018 — ῥάχις
rhachis · a spine · Greek