4 occurrences in 4 dictionaries

Reference: Matred

Fausets

Hastings

The mother-in-law (?) of Hadar (Gn.) or Hadad (Ch.), one of the kings of Edom, Ge 36:39 = 1Ch 1:50. In Gn. the Septuagint and Pesh. make Matred the son not the daughter of Me-zahab (wh. see).

Morish

Mother of Mehetabel the wife of Hadad, or Hadar, king of Edom. Ge 36:39; 1Ch 1:50.

Smith

Ma'tred

(pushing forward) daughter of Mezahab and mother of Mehetabel, who was wife of Hadar or Hadad of Pau, king of Edom.

Ge 36:39; 1Ch 1:50