Boyd’s Bible Dictionary:

(hairy). (1) A Horite chief (Gen. 36:2121And Dishon, and Ezer, and Dishan: these are the dukes of the Horites, the children of Seir in the land of Edom. (Genesis 36:21); Deut. 2:1212The Horims also dwelt in Seir beforetime; but the children of Esau succeeded them, when they had destroyed them from before them, and dwelt in their stead; as Israel did unto the land of his possession, which the Lord gave unto them. (Deuteronomy 2:12)). (2) Land or country corresponding with valley and mountains of Arabah, stretching from the Dead Sea to the Gulf of Akaba (Gen. 14:6; 32:3; 33:14-166And the Horites in their mount Seir, unto El-paran, which is by the wilderness. (Genesis 14:6)
3And Jacob sent messengers before him to Esau his brother unto the land of Seir, the country of Edom. (Genesis 32:3)
14Let my lord, I pray thee, pass over before his servant: and I will lead on softly, according as the cattle that goeth before me and the children be able to endure, until I come unto my lord unto Seir. 15And Esau said, Let me now leave with thee some of the folk that are with me. And he said, What needeth it? let me find grace in the sight of my lord. 16So Esau returned that day on his way unto Seir. (Genesis 33:14‑16)
). The region was first occupied by the Horites, and fell into possession of Esau and his posterity (Gen. 36:8-98Thus dwelt Esau in mount Seir: Esau is Edom. 9And these are the generations of Esau the father of the Edomites in mount Seir: (Genesis 36:8‑9)). Hence Seir and Edom are sometimes spoken of as identical. The Israelites, when refused permission to march through Edom to Moab, marched round the granite ranges of Seir and entered Moab by the east and north. (3) A boundary mark of Judah (Josh. 15:1010And the border compassed from Baalah westward unto mount Seir, and passed along unto the side of mount Jearim, which is Chesalon, on the north side, and went down to Beth-shemesh, and passed on to Timnah: (Joshua 15:10)).

Strong’s Dictionary of Hebrew Words:

formed like 8163; rough; Seir, a mountain of Idumaea and its aboriginal occupants, also one in Palestine
KJV Usage:

Jackson’s Dictionary of Scripture Proper Names:

shaggy hairy: goat-like

Potts’ Bible Proper Names:

Rough; hairy; shaggy:―name of two mountains, also a Horite chief, Gen. 36:20. {Hirsutus}