unknown

UK: ʌnˈnəʊn | US: ʌnˈnoʊn

Definition
  1. adj. not known or familiar; not identified or understood

  2. n. a person or thing that is not known or recognized

Structure
un <not>known <recognized>
Etymology

The word "unknown" combines the Old English prefix "un-" (meaning "not") with the past participle "known" (from Old English "cnāwan," meaning "to perceive or recognize"). The prefix "un-" is a prolific negator in English, while "known" traces back to Proto-Germanic "*knewan," related to perception and awareness. Together, they form a straightforward negation of familiarity or recognition, a concept preserved since Old English.

Examples
  1. The artist remained unknown until her work went viral.

  2. The cause of the malfunction is still unknown.

  3. He ventured into unknown territory without a map.

  4. The book explores the unknown depths of the ocean.

  5. Fear of the unknown often holds people back.