"intellect, intelligence," 1820, from Greek noēsis "intelligence, thought," from noein "to see, perceive, have mental perception," from noos "mind, thought" which is of uncertain origin.

"pertaining to, performed by, or originating in the intellect," 1650s, from Greek noētikos "intelligent," from noēsis "a perception, intelligence, thought" (see noesis). Related: Noetical (1640s).