In Aristotelian philosophy, the essential form or nature that makes a thing what it is, as opposed to matter. Contrasts with Platonic idea.
from Ancient Greek eidos
See also: 形相
In Platonism, the eternal, perfect Form or Idea of which material things are imperfect copies. Often used alongside イデア.
See also: イデア
Aristotle called the essence of things eidos.
In Plato's philosophy, eidos is an eternal and unchanging reality.