Fausset's Bible Dictionary

1. On his father's side, of Judah; on his mother's side, of Manasseh. Son of Segub, who was son of Hezron by his third wife, daughter and heiress in part of Machir (father of Gilead) of Manasseh (1Ch 2:21-22-23; Deu 3:14-15). His designation from his mother, not his father, was probably owing to his settling in Manasseh E. of Jordan. His brilliant exploit was, he took Argob or Trachonitis, the Lejah, and called from his own name certain villages or groups of tents ("kraals"), 23 originally, Havoth Jair (Num 32:41), afterward increased to 30 (Jdg 10:4).

3. A Benjamite, son of Kish, father of Mordecai (Est 2:5).

4. A different Hebrew name, though in English Jair, or Jeer (Hebrew text or kethib). Father of Elhanan, one of David's heroes who slew Lahmi, Goliath's brother (1Ch 20:5).