Easton's Bible Dictionary: M. G. Easton, M.A., D.D.

Hadar

Adod, brave(?).

1. A son of Ishmael (Gen. 25:15); in 1 Chr. 1:30 written Hadad.
2. One of the Edomitish kings (Gen. 36:39) about the time of Saul. Called also Hadad (1 Chr. 1:50, 51).

It is probable that in these cases Hadar may be an error simply of transcription for Hadad.