Impercipient :: Impercipient (a.) Not perceiving, or not able to perceive..
Percipiency :: Percipiency (n.) The faculty, act or power of perceiving; perception..
Percipient :: Percipient (a.) Having the faculty of perception; perceiving; as, a percipient being..
Percipient :: Percipient (n.) One who, or that which, is percipient..