Lewis & Short

pĭtheus, ĕi and ĕos (also pĭthus, i, and pĭthĭas, ae), m., = πιθεύς, πίθος, and πιτθιας, a barrel-shaped comet, Plin. 2, 25, 22, § 90; Sen. Q. N. 1, 14, 1; App. de Mundo, p. 64.