Easton's Bible Dictionary (1897)
Leaving, one of Abraham’s sons by Keturah (Gen. 25:2).
Smith's Bible Dictionary (1863)
(left behind), a son of Abraham and Keturah, (Genesis 25:2; 1 Chronicles 1:32) and the progenitor of a tribe of northern Arabia.
Hastings' Dictionary of the Bible (1898) & Schaff's Bible Dictionary
ISH'BAK (leaving behind), a son of Abraham by Keturah. Gen 25:2; 1 Chr 1:32. From him sprang the northern Arabians.
Hitchcock's Bible Names (1869)
who is empty or exhausted