duckness

noun

1. (uncountable)The quality of being a duck.

   “According to this way of thinking, one knows what DUCK is because ducks have something in common — their duckness categorized according to how they walk, talk, and so on.”

   “However, while both designer and creature seem intent on zeroing in on real and pure duckness, this state remains elusive. The Duck is always on the move (both spatially and in terms of its nature), now drawing near, now drawing away […]”

   “When one points out that these lines must be taken as the bill and the eye as looking in this direction, one is not marshaling evidence for duckness, but trying to get another to see the picture as a duck.”