Boyd’s Bible Dictionary:

Descendants of Heth
(Gen. 10:15; 25:9; Josh. 3:10; 2 Sam. 11:3).

Concise Bible Dictionary:

The descendants of Heth, a son of Canaan, and hence descendants of Ham: a numerous race who inhabited Palestine. In God’s covenant with Abraham their territory was to be possessed by his descendants (Gen. 15:20). On the death of Sarah, Abraham bought the field and cave of Machpelah from the Hittites. His intercourse and contract with them show that they were a civilized race, used to commercial transactions (Gen. 23:3-20). This was near or at Hebron in the south of Palestine, whereas other passages speak of them in the north, between the Lebanon and the Euphrates, which was probably where they originally settled (Josh. 1:4); and there are intimations that they continued a powerful and warlike race after Palestine was possessed by Israel (1 Kings 10:29; 2 Kings 7:6). Ahimelech and Uriah, eminent men in the time of David, were Hittites (1 Sam. 26:6; 2 Sam. 23:39).
In various parts of Palestine and Syria monuments have been found of the Hittites, and in Egypt there are records of a long defensive treaty that was made between the Egyptians and the Hittites, showing that the latter were an important race. The Tell Amarna tablets show that they seized upon Damascus then held by Egypt. Letter after letter urged Egypt to come to the rescue. Their features even are now well understood on the monuments, being described as a people with yellow skins and “mongoloid” features, receding foreheads, oblique eyes, and protruding upper jaws. There are inscriptions which show their language; but this at present is only beginning to be deciphered.

Jackson’s Dictionary of Scripture Proper Names:

patronymic of Heth