Lewis & Short

Thērăsĭa, ae, f., = Θηρασία,

  1. I. a small island in the Ægean Sea, opposite to Thea, westward, still called Therasia, Plin. 2, 87, 89, § 202; 4, 12, 23, § 70; Sen. Q. N. 6, 21, 1.
  2. II. One of the Lipari islands near Sicily, now Vulcanello, Plin. 3, 9, 14, § 93; Mart. Cap. 6, § 648.