Featherless Biped Meaning

(idiomatic, usually humorous) A human being.

Example: 1863, Charles Reade, Hard Cash, ch. 12:
  The schoolmen, or rather certain of the schoolmen—for nothing is much shallower than to speak of all those disputants as one school—defined woman, "a featherless biped vehemently addicted to jealousy."
1889, Charles Kendall Adams, "Discipline in American Colleges", The North American Review, vol. 149, no. 392, p. 15:
  But the college student is often neither a boy nor a man. . . . Reference is here made, of course, to that species of featherless biped which at times, especially when taken alone, seems to show many of the characteristics of rational intelligence, but which, when merged into a crowd of its fellows, is apt, on the least provocation, to part with its power of thought and lapse into all manner of irrational ways.
1933, Arthur O. Lovejoy, The Great Chain of Being (1964 ed.), ISBN 9780674361539, p. 102:
  There were, of course, other elements in the medieval Christian system which were adapted to breed in the featherless biped a high sense of his cosmic importance and of the momentousness of his own doings.
2008 June 16, Dan Tynan, "Bill Gates: 10 Memorable Moments," ABC News (retrieved 9 Sep 2010):
  The day Microsoft went public, Gates became an instant megamillionaire . . . . But it wasn't until July 17, 1995, that Forbes magazine named him the richest featherless biped on the planet.