Etymology First use appears c. 1573 in the sense of "aware of wrongdoing".https://web.archive.org/web/20220714064352/https://www.lexico.com/definition/conscious From Latin cōnscius (“conscious, conscious of guilt”), itself from con- (a form of com- (“together”)) + scīre (“to know”) + -us.
1
Alert, awake; with one's mental faculties active.
The noise woke me, but it was another few minutes before I was fully conscious.
2
Aware of one's own existence; aware of one's own awareness.
The best indicator of your level of consciousness is how you deal with life's challenges when they come. Through those challenges, an already unconscious person tends to become more deeply unconscious, and a conscious person more intensely conscious.1999, Eckhart Tolle, The Power of Now, Hodder and Stoughton, pages 61–62:
Only highly intelligent beings can be fully conscious.
3
Aware of, sensitive to; observing and noticing, or being strongly interested in or concerned about.
I was conscious of a noise behind me. a very class-conscious analysis
Here, in the transept and choir, where the service was being held, one was conscious every moment of an increasing brightness; colours glowing vividly beneath the circular chandeliers, and the rows of small lights on the choristers' desks flashed and sparkled in front of the boys' faces, deep linen collars, and red neckbands.1918, W[illiam] B[abington] Maxwell, chapter V, in The Mirror and the Lamp, Indianapolis, Ind.: The Bobbs-Merrill Company, →OCLC:
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Once again the animals were conscious of a vague uneasiness.1943 November – 1944 February (date written; published 1945 August 17), George Orwell [pseudonym; Eric Arthur Blair], Animal Farm […], London: Secker & Warburg, published May 1962, →OCLC:
Furthermore, the military operator is far less conscious of budgetary constraints than is the civilian consumer.1955, Arthur Smithies, The Budgetary Process in the United States, page 290:
4
Deliberate, intentional, done with awareness of what one is doing.
He candidly confesses that it is an effort to account for Joseph Smith upon some other hypothesis than that he was a conscious fraud, bent on deceiving mankind.1907, Brigham Henry Roberts, Defense of the Faith and the Saints, volume 1, page 43:
Start fresh, try and learn from past mistakes, make a conscious effort to be a better person.2015, Jamie Kornegay, Soil: A Novel, page 214:
5
Known or felt personally, internally by a person.
conscious guilt
6
Rare Self-conscious, or aware of wrongdoing, feeling guilty.
He coloured very deeply, and giving a momentary glance at Elinor, replied, “Yes; it is my sister’s hair. The setting always casts a different shade on it, you know.” Elinor had met his eye, and looked conscious likewise..1811, [Jane Austen], chapter XVIII, in Sense and Sensibility […], volume I, London: […] C[harles] Roworth, […], and published by T[homas] Egerton, […], →OCLC, page 229:
They found Aunt Carrol with the old lady, both absorbed in some very interesting subject ; but they dropped it as the girls came in, with a conscious look which betrayed that they had been talking about their nieces.1869, Louisa M[ay] Alcott, Little Women: […], 2nd part, Boston, Mass.: Roberts Brothers, →OCLC:
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c. 1634, John Dryden (translator), Richard Crashaw, Epigrammatum sacrorum liber The conscious water saw its God, and blushed.
Etymology First use appears c. 1573 in the sense of "aware of wrongdoing".https://web.archive.org/web/20220714064352/https://www.lexico.com/definition/conscious From Latin cōnscius (“conscious, conscious of guilt”), itself from con- (a form of com- (“together”)) + scīre (“to know”) + -us.
1
The part of the mind that is aware of itself; the consciousness.