unknown
- 01 B2 Upper Intermediate
adj.not known, identified, or familiar to people.
adj.not known, identified, or familiar; often used postpositionally in specific phrases like 'reasons unknown'.
Simple“The letter was sent by an unknown person with no return address.”
In context“The painting was attributed to an unknown artist from the seventeenth century, though recent stylistic analysis suggests a student of Rembrandt.”
Synonyms - 02 B2 Upper Intermediate
n.a place, situation, or fact that nobody knows anything about yet.
n.an unexplored or unidentified place, situation, or realm of knowledge; often used with the definite article 'the'.
Simple“Space travel is a journey into the unknown for most of us.”
In context“The explorers faced the great unknown with a mixture of trepidation and scientific curiosity, unsure of what the deep-sea trenches might reveal.”
SynonymsAntonyms - 03 C1 Advanced
n.a person who is not famous or whose identity is not known.
n.an individual who lacks fame, social standing, or a public identity.
Simple“He was a complete unknown before he won the national talent show.”
In context“The candidate was a political unknown until a series of viral debates propelled her to the forefront of the national conversation.”
- 04 B2 Upper Intermediate
n.a symbol, like x or y, that represents a number you need to find.
n.a quantity or variable in a mathematical equation whose value is initially unspecified and must be determined.
Simple“In the equation 2x + 5 = 11, x is the unknown.”
In context“The physicist introduced a second unknown into the formula to account for the unexpected variance in gravitational pull during the experiment.”
“The victim was transported to hospital via an emergency run by paramedics with unknown injuries.”
“I had to tell him to put it out.” The cause of the Blaenavon fire is still unknown, but across the country arson arrests have been made in relation to this summer’s fires.”
From Middle English unknowen, uniknowen, uniknowe, from Old English unġecnāwen (“unknown”), equivalent to un- + known.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.