c.1600, "knowing, privy to," from Latin conscius "knowing, aware," from conscire (see conscience); probably a loan-translation of Greek syneidos. A word adopted from the Latin poets and much mocked at first. Sense of "active and awake" is from 1837.
conscious con·scious (kŏn'shəs)
adj.
Having an awareness of one's environment and one's own existence, sensations, and thoughts.
Intentionally conceived or done; deliberate.