[ide.al.ism] n (1796) 1 a (1): a theory that ultimate reality lies in a realm transcending phenomena (2): a theory that the essential nature of reality lies in consciousness or reason b (1): a theory that only the perceptible is real (2): a theory that only mental states or entities are knowable
2. a: the practice of forming ideals or living under their influence b: something that is idealized
3: literary or artistic theory or practice that affirms the preeminent value of imagination as compared with faithful copying of nature--compare realism