Nou'me-non, n.

n. [Gr. νοούμενον, the thing perceived, p. pr. pass. of νοεῖν, to perceive, νοῦς, the mind.] (Metaph.) The of itself unknown and unknowable rational object, or thing in itself, which is distinguished from the phenomenon in which it occurs to apprehension, and by which it is interpreted and understood;—so used in the philosophy of Kant and his followers.