Lewis & Short

Pentheus, ĕi and ĕos, m., = Πενθεύς, son of Echion and Agave, grandson of Cadmus, and king of Thebes; having treated with contempt the rites of Bacchus, he was torn in pieces by his mother and her sisters when under the influence of the god, Ov. M. 3, 514; Prop. 3, 17 (4, 16), 24; 3 (4), 22, 33; Ov. Tr. 5, 3, 40; Hor. Ep. 1, 16, 73; id. C. 2, 19, 14.
Hence,

  1. A. Penthēĭus, a, um, adj., of or belonging to Pentheus, Penthean: mater, Sid. Carm. 22, 94.
  2. B. Penthēus, a, um, adj., = Πενθεῖος, of or belonging to Pentheus, Penthean, Stat. Th. 2, 575.
  3. C. Penthīdes, ae, m., = Πενθείδης, a male descendant of Pentheus, Ov. Ib. 449 and 609.