hyle ancient Greek term for matter. Aristotle brought the word into use in philosophy by contrast with the term for form, and as designating one of the four causes. By hyle Aristotle usually means ‘that out of which something has been made’, but he can also mean by it ‘that which has form’. In Aristotelian philosophy hyle is sometimes also identified with potentiality and with substrate. Neoplatonists identified hyle with the receptacle of Plato. See also ARISTOTLE , FORM, HYLOMORPHISM , METAPHYSICS , SUBSTANC. P.Wo.