From New Latin papilionaceus (from Latin pāpiliō (butterfly)) +‎ -ous. In scientific sense, after Papilionaceae (family name).


papilionaceous (comparative more papilionaceous, superlative most papilionaceous)

  1. (obsolete) Pertaining to a butterfly or butterflies. [17th–19th c.]
  2. (botany) Having a corolla in the form of a butterfly, with prominent wing-like petals; (generally) pertaining to the Faboidea (Papilionoidea) family of plants. [from 17th c.]
    • 1962, WH Auden & Elizabeth Mayer, translating JW Goethe, Italian Journey, Penguin 1970, p. 261:
      [T]he broad road is lined with wild bushes and tangled shrubs lavishly decked with brilliant blossoms: the lentisk, so covered with yellow, papilionaceous flowers [transl. Schmetterlingsblumen] that not a green leaf is visible…
  3. (figuratively) Like a butterfly; showy; capricious. [from 19th c.]
    • 2000, Evening Standard, 3 April:
      Ali G was a glorious, comedic butterfly, but it's my sad duty to report that his exquisitely papilionaceous character is currently being broken upon a wheel.