Lewis & Short

rēgĭ-fŭgĭum, ii, n. [rex-fuga, the king’s flight], a festival celebrated on the 24th of February, to commemorate the expulsion of the kings, Aus. Ecl. Fer. Rom. 13; Fest. p. 278 Müll.; Paul. ex Fest. p. 279 ib.; Kalend. Maff. ap. Orell. Inscr. II. p. 384; called regis fuga, Ov. F. 2, 685.