\Prog"ne\, n. [L., a swallow, traditionally said to be
fr. Progne (The sister of Philomela), who was changed into a
swallow, Gr. ?.] (Zo["o]l.)
(a) A swallow.
(b) A genus of swallows including the purple martin. See
    {Martin}.
(c) An American butterfly ({Polygonia, or Vanessa, Progne}).
    It is orange and black above, grayish beneath, with an
    L-shaped silver mark on the hind wings. Called also {gray
    comma}.