Per-çēp'tion, n.

n. [Lat. perceptio, Fr. perception, Sp. percepcion, It. percezione. See PERCEIVE.]

1. The act of perceiving; cognizance by the senses or intellect; apprehension by the bodily organs or by the mind of what is presented to them; discernment; cognition.
2. (Psychology.) The faculty of perceiving; the faculty or peculiar part of man's constitution, by which he has knowledge through the medium or instrumentality of the bodily organs; the act of apprehending material objects or qualities through the senses. As thus used, perception proper, or the act of knowledge, is distinguished from sensation proper, or the sensible affection which is its invariable accompaniment. Sir W. Hamilton.
3. The state of being affected, or capability of being affected, by something external; sensation. [Obs.]

This experiment discovers perception in plants. Bacon. ☞ “The word perception is, in the language of philosophers previous to Reid, used in a very extensive signification. By Descartes, Malebranche, Locke, Leibnitz, and others, it is employed in a sense almost as unexclusive as consciousness, in its widest signification. By Reid this word was limited to our faculty acquisitive of knowledge, and to that branch of this faculty whereby, through the senses, we obtain a knowledge of the external world. But his limitation did not stop here. In the act of external perception he distinguished two elements, to which he gave the names of perception and sensation. He ought perhaps to have called these perception proper and sensation proper, when employed in his special meaning.” Sir W. Hamilton.