Lewis & Short

vappo, ōnis, m. [root vap-, to flutter; cf. Gr. ήπίολος, moth], a moth, butterfly, Lucr. (or Lucil.) Fragm. ap. Prob. p. 1450 P. (v. Lindem. Corp. Gram. I. p. 109, n. 32; cf. Lachm. ad Lucr. 2, p. 165 sq.).