Hadar

Adod, brave(?). A son of Ishmael (Genesis 25:15); in 1 Chronicles 1:30 written Hadad.

One of the Edomitish kings (Genesis 36:39) about the time of Saul. Called also Hadad (1 Chronicles 1:50,51).

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

Source: Easton's Bible Dictionary
Hadar

[HADAD]

Source: Smith's Bible Dictionary