Emily Dickinson Lexicon

PER-CEP'TION, n. [L. perceptio. See Perceive.]

1. The act of perceiving or of receiving impressions by the senses; or that act or process of the mind which makes known an external object. In other words, the notice which the mind takes of external objects. We gain a knowledge of the coldness and smoothness of marble by perception.
2. In philosophy, 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. – Reid. Encyc.
3. Notion; idea. – Hall.
4. The state of being affected or capable of being affected; by something external. This experiment discovers perception in plants. – Bacon.