When you're unconscious you're passed out or asleep. Anything going on in the body that we're not aware of can also be called unconscious.

Being unconscious can be very nice, especially when you're in the middle of a deep sleep. But if you're unconscious because you fainted or got hit in the head, that's not so good. Unconscious people aren't aware of what's going on, and they can't talk or do things — except maybe for sleepwalking and sleeptalking. There are also unconscious thoughts and desires: things going on in the mind that you don't know about.

Definitions of unconscious

adj not conscious; lacking awareness and the capacity for sensory perception as if asleep or dead

“lay unconscious on the floor”
in a state of sleep
incognizant, unaware
(often followed by `of') not aware
unconscious from a blow or shock or intoxication
in a state of deep and usually prolonged unconsciousness; unable to respond to external stimuli
(used of things) lacking sense or awareness
insensible, senseless
unresponsive to stimulation
KO'd, kayoed, knocked out, out, stunned
knocked unconscious by a heavy blow
concerning mental functioning that is not represented in consciousness
in a state of partial coma
just below the level of consciousness
incapable of physical sensation
involuntary, nonvoluntary, unvoluntary
not subject to the control of the will
knowing and perceiving; having awareness of surroundings and sensations and thoughts
not in a state of sleep; completely conscious
aware, cognisant, cognizant
(sometimes followed by `of') having or showing knowledge or understanding or realization or perception
self-aware, self-conscious
aware of yourself as an individual or of your own being and actions and thoughts
partially conscious; not completely aware of sensations
consciously perceiving
sensible, sensitive
able to feel or perceive
of your own free will or design; done by choice; not forced or compelled
show more antonyms...

adj without conscious volition

involuntary, nonvoluntary, unvoluntary
not subject to the control of the will

adj (followed by `of') not knowing or perceiving

“"happily unconscious of the new calamity at home"- Charles Dickens”
incognizant, unaware
(often followed by `of') not aware

n that part of the mind wherein psychic activity takes place of which the person is unaware

unconscious mind
Type of:
brain, head, mind, nous, psyche
that which is responsible for one's thoughts and feelings; the seat of the faculty of reason

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