What's the "een" in Halloween?
1796, "object of intellectual intuition" (opposed to a phenomenon), term introduced by Kant, from Greek noumenon "that which is perceived," neuter passive present participle of noein "to apprehend, perceive by the mind" (from noos "mind"). With passive suffix -menos.
in the philosophy of Immanuel Kant, the thing-in-itself (das Ding an sich) as opposed to what Kant called the phenomenon-the thing as it appears to an observer. Though the noumenal holds the contents of the intelligible world, Kant claimed that man's speculative reason can only know phenomena and can never penetrate to the noumenon. Man, however, is not altogether excluded from the noumenal because practical reason-i.e., the capacity for acting as a moral agent-makes no sense unless a noumenal world is postulated in which freedom, God, and immortality abide.