Mahalath
The name Mahalath belongs to two women in the genealogies and surfaces a third time as a musical term in two Psalm superscriptions. The umbrella collects all three.
Esau's Wife
After learning that his Canaanite wives displease his parents, Esau goes to Ishmael for a third wife: "Mahalath the daughter of Ishmael Abraham's son, the sister of Nebaioth, to be his wife" (Gen 28:9). The same woman is named Basemath in the parallel genealogy of Esau's wives — "and Basemath Ishmael's daughter, sister of Nebaioth" (Gen 36:3) — the two names refer to the same person.
Rehoboam's Wife
A generation after David, a granddaughter through Jerimoth bears the same name: "And Rehoboam took himself a wife, Mahalath the daughter of Jerimoth the son of David, [and of] Abihail the daughter of Eliab the son of Jesse" (2Ch 11:18). She is doubly Davidic — through Jerimoth on one side and, through her mother Abihail, through David's brother Eliab on the other.
A Musical Term in the Psalter
The same Hebrew word stands at the head of two psalms, marking a tune or musical setting rather than a person. Psalm 53 opens, "For the Chief Musician; set to Mahalath. Maschil of David" (Ps 53:1). Psalm 88 carries an expanded form: "A Song, a Psalm of the sons of Korah; for the Chief Musician; set to Mahalath Leannoth. Maschil of Heman the Ezrahite" (Ps 88:1). In both, "set to Mahalath" sits alongside other technical superscription notes (Chief Musician, Maschil) that govern performance rather than content.