1640s, "perceiving directly and immediately," from French intuitif or directly from Medieval Latin intuitivus, from intuit-, past-participle stem of Latin intueri "look at, consider," from in- "into" (from PIE root *en "in") + tueri "to look at, watch over," a word of uncertain origin. Meaning "self-evident" is from 1833. Related: Intuitively; intuitiveness.

"sense-perception," 1833 as a German word in English, nativized from 1848, from German Anschauung "mode of view," literally "a looking at," from anschauen "to look at," from Middle High German aneschouwen, from an (see on) + Old High German scouwon "to look at" (from PIE root *keu- "to see, observe, perceive"). A term in Kantian philosophy.

late 15c., perspicuite, of things, "clearness, transparency" (a sense now obsolete); 1540s of words or expressions, "quality of being clear to the mind; quality by which the meaning can be seen through the words," from Old French perspicuité and directly from Latin perspicuitas "transparency, clearness," from perspicuus "transparent," from perspicere "look through, look closely at" (see perspective).

"a lowering or wrinkling of the brows, as in anger or displeasure; a malevolent, lowering look," c. 1500, from scowl (v.).