Hemam
Hemam is one of the sons of Lotan in the Horite genealogy of Edom. The umbrella term is the older form; in the UPDV the name appears once as Heman and once, in the parallel Chronicles list, as Homam.
Son of Lotan in the Horite Line
In the Edomite/Horite genealogy, Lotan has two sons and a sister: "And the sons of Lotan were Hori and Heman. And Lotan's sister was Timna" (Gen 36:22). The wider context is the line of the Horite chiefs of the land of Seir; Lotan is a son of Seir, and Hori and Heman (= Hemam) are his offspring.
The Parallel Spelling: Homam
The same family is repeated in the Chronicler's opening genealogy, with a slight orthographic shift: "And the sons of Lotan: Hori, and Homam; and Timna was Lotan's sister" (1 Chr 1:39). The two rosters match name-for-name — Hori and the Hemam/Homam figure are the sons, Timna is Lotan's sister — confirming that Hemam (Genesis), Heman (UPDV at Gen 36:22), and Homam (Chronicles) are spellings of one Horite descendant.