Unknown

Part of speech: adjective, noun

Pronunciation: /ʌn(ˈn)əʊn/

Definitions

1. not recognized, identified, or familiar; lacking information or awareness about something
2. not recognized or identified by anyone
3. lacking familiarity or knowledge about a subject

Etymology: The English word "unknown" is a plain formation: the prefix "un-", meaning "not", attached to "known." What makes it more than a simple negation is how old it is. Its ancestor in Old English was "unġecnāwen," built from "ġecnāwen," the past participle of "cnāwan," "to know," so the sense "not known" was already in place more than a thousand years ago. The word then passed through Middle English forms such as "unknowen" and "uniknowe," which were gradually reshaped into the spelling we use today. The same pattern runs through much of the vocabulary here. English has long attached "un-" to participles to make negative adjectives, so "unknown" sits alongside older and newer words such as "unseen," "unheard," and "untold." Its meaning is also flexible in a way the prefix alone would not predict. As an adjective it can describe something that has never been identified, as in an "unknown soldier," or simply a person or thing a listener has not met, and as a noun it names the unidentified or the unexplored, as in "a leap into the unknown."

Synonyms: unfamiliar, strange, obscure

Antonyms: known, familiar