SEIR . 1 . The name of a mountainous district east of the ‘Arabah, peopled by the Edomites. It was originally occupied by Horites or ‘cave-dwellers’ ( Genesis 14:6 ). Mt. Seir is practically synonymous with Edom (cf. Genesis 32:3 ‘the land of Seir, the field of Edom’). 2 . ‘Mt. Seir’ mentioned in Joshua 15:10 among the points defining the boundaries of Judah. The name may still be preserved in that of the ruins at Sârîs , S.W. of Kiriath-jearim.