Source : Webster's Revised Unabridged Dictionary (1913)

Turnus \Tur"nus\, n. [NL., fr. L. Turnus, the king of the
   Rutuli, mentioned in the [AE]neid.] (Zo["o]l.)
   A common, large, handsome, American swallowtail butterfly,
   now regarded as one of the forms of {Papilio, or Jasoniades,
   glaucus}. The wings are yellow, margined and barred with
   black, and with an orange-red spot near the posterior angle
   of the hind wings. Called also {tiger swallowtail}. See
   Illust. under {Swallowtail}.