Who and what is…
Hebrew: שֵׂעִיר —transliteration: Seir
Seir was the name of 2 mountain ranges and a Biblical man:
Seir, a Horite man
Seir mountains of Edom
This is an ancient name of a mountainous region occupied by the Edomites, extending along the eastern side of the Arabah from the southeastern extremity of the Dead Sea to near the Akabah, or the eastern branch of the Red Sea (Gulf of Aqaba).
It was originally occupied by the Horites (Genesis 14:6), who were afterwards driven out by the Edomites (Genesis 32:3; 33:14, 16). It was allotted to the descendants of Esau (Deuteronomy 2:4, 22; Joshua 24:4; 2 Chronicles 20:10; Isaiah 21:11; Ezek. 25:8).
The land of Seir, mountain range (not the Edomite range)
It lays between the Wady Aly and the Wady Ghurab (Joshua 15:10).