unconsciousness

IPA/ʌnˈkɒnʃəsnəs/
KK[ˌʌnkˈɑnʃəsnɪs]IPA/ʌnˈkɑːnʃəsnəs/

unconsciousness — noun

1. a sleeplike state caused by injury, illness, or drugs, in which a person cannot

1.nounB2
Definition

a sleeplike state caused by injury, illness, or drugs, in which a person cannot see, hear, feel, or respond to what is happening around them

Example

The cyclist was found lying on the road in a state of unconsciousness after the collision.

prepositional phrase: in a state of unconsciousness

Patients who slip into unconsciousness after a head injury need immediate medical attention.

verb collocation: slip into unconsciousness

Common collocations
  • fall into unconsciousness
  • lapse into unconsciousness
  • regain consciousness
  • loss of consciousness
  • state of unconsciousness
  • deep unconsciousness
Synonyms
  • coma

    a much deeper, longer-lasting state of unconsciousness, usually from severe brain injury

  • stupor

    a state of near-unconsciousness where a person is barely responsive, often caused by alcohol or drugs

Antonyms
  • consciousness

    the normal waking state of being aware and responsive

Grammar Patterns

unconsciousness + verb: sets in / occurs / lasts

Usage Note

Uncountable; typically used with verbs like fall into, lapse into, slip into, or recover from. This sense belongs to medical or emergency contexts — distinguish from the psychological concept of the unconscious mind.

Common Mistakes

He was in unconsciousness for three hours.
He was unconscious for three hours.
The adjective unconscious is preferred for describing a person's state; the noun form is less natural with am/is/are.
The doctor studied the patient's unconsciousness.
The doctor examined the unconscious patient.
Avoid using the noun form where the adjective would sound more natural.

unconsciousness — adjective

Word family

Synonym discussion

Sense: adjective/5

All four words describe a lack of knowledge or attention, but they differ in degree and connotation. Unaware (the most neutral and common) simply means not knowing about something: 'She was unaware of the time.' Oblivious is stronger and often suggests that the person should have noticed but did not, with a slightly critical tone: 'He was oblivious to the crying baby next to him.' Ignorant can mean lacking specific knowledge — 'ignorant of the law' — but carries a social stigma when applied to people rather than facts, so use it carefully. Heedless is more literary and implies active disregard or carelessness: 'heedless of the warnings.' For everyday situations, unaware is the safest choice; for workplace or academic writing about bias or assumptions, unconscious (the headword itself) is more precise than any of these.

Common collocations

Phrases

  • loss of consciousness
  • state of unconsciousness
  • unconscious mind
  • unconscious bias training

Prepositions

Etymology

LatinEnglish

Formed in English by combining the prefix un- (meaning 'not') with conscious (from Latin conscius 'knowing, aware') and the noun suffix -ness (which turns adjectives into nouns meaning 'a state or quality'). The word first appeared in the late 18th century, originally in philosophical contexts describing the absence of awareness. The psychological sense — referring to a part of the mind — developed in the mid-19th century and was popularised by Sigmund Freud and Carl Jung in the early 1900s.

First known use

1712

1712, in the meaning defined at sense 2a Noun