Probably from an obsolete oro (to rise or "rear"; perhaps akin to airo; compare ornis); a mountain (as lifting itself above the plain): -hill, mount(-ain).

see GREEK airo

see GREEK ornis

ὄρει (orei) − 11 Occurrences

ὄρεσιν (oresin) − 4 Occurrences

ὀρέων (oreōn) − 1 Occurrence

ὄρη (orē) − 7 Occurrences

ὄρος (oros) − 28 Occurrences

ὄρους (orous) − 12 Occurrences