Pronunciation: (nOO'mu-non"),[key] —n., —pl.-naPronunciation: (-nu).[key] 1. the object, itself inaccessible to experience, to which a phenomenon is referred for the basis or cause of its sense content.
2. a thing in itself, as distinguished from a phenomenon or thing as it appears.
3. Kantianism.something that can be the object only of a purely intellectual, nonsensuous intuition.