What does clue mean?
A clue is a piece of evidence or information that helps someone solve a problem, answer a question, or understand a situation. In detective fiction and real investigations alike, clues are the small details — fingerprints, overheard remarks, inconsistencies — that gradually point toward a solution. Beyond its literal use, clue has taken on a broader figurative sense in everyday English: saying you haven't 'got a clue' means you are completely unaware or ignorant of something, while being 'clued up' or 'clued in' means being well informed. The word carries no strong connotation of formality and appears comfortably in both casual conversation and technical writing. Its origin adds a memorable layer: it derives from 'clew,' meaning a ball of thread, recalling the mythical thread Ariadne gave Theseus to escape the Minotaur's labyrinth — making a clue literally a thread that guides one out of confusion toward an answer.
A piece of evidence or information that helps solve a problem or unravel a mystery; also, a general hint or understanding of something.
"Each clue she uncovered brought her closer to the truth about her family's past."
Often used in plural when referring to multiple pieces of evidence; the idiomatic phrase 'haven't got a clue' expresses complete lack of knowledge.
To give someone information or insight into something, usually in the phrasal form 'clue in' (informal).
"Can you clue me in on what happened at the meeting?"
Almost always used with the particle 'in'; considered informal register.
Standard pluralization; commonly used when discussing multiple pieces of evidence.
"The investigators collected several clues before identifying the suspect."
The word 'clue' comes from Greek mythology: Ariadne's thread that guided Theseus out of the Minotaur's labyrinth gave us our word for any piece of evidence that leads us to an answer.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of clue
The word clue originated as a variant spelling of clew, meaning a ball of thread or yarn, which traces back through Middle English to Old English cliewen. Its modern figurative sense emerged in the early 17th century, inspired by the classical myth of Theseus, who followed a thread given by Ariadne to find his way out of the Minotaur's labyrinth. From this image of a guiding thread, clue came to mean anything that points the way to a solution or discovery. The spelling clue became standard over time, while clew survives mainly in nautical contexts.
Related word forms
How clue is actually used
Common in both formal detective/crime contexts and informal speech. The informal phrase 'not have a clue' implies complete ignorance of something. As a verb, 'to clue someone in' means to inform them about something.
Easily confused with clue
Clew is the older spelling and still refers specifically to a ball of thread or yarn, or to the lower corner of a sail, whereas clue is now used for hints or evidence.