This idiom describes making every possible effort, exploring all options, or investigating thoroughly to achieve a goal or uncover the truth, as if turning over every stone to find something hidden. It conveys relentless determination, meticulousness, or exhaustive action, used in investigative, professional, or personal contexts to praise or encourage thoroughness. The phrase carries a tone of resolve, diligence, or urgency, reflecting cultural values of persistence and attention to detail, particularly in complex or critical tasks. It resonates in societies that prize comprehensive solutions or justice, capturing the human drive to exhaust all possibilities, and often implies a commitment to leaving nothing to chance, making it a powerful metaphor for dedication and rigor.

The phrase has roots in ancient Greece, derived from a story in Herodotus’ *Histories* (5th century BCE), where Polycrates searches for a treasure by ‘turning every stone.’ It was adapted into English by the 16th century, with an early use in John Heywood’s 1546 *Proverbs*: ‘Leave no stone unturned.’ The idiom gained traction in the 17th century, reflecting Renaissance emphasis on inquiry, as seen in Francis Bacon’s essays on exploration. Its use grew in 19th-century British and American literature, particularly in detective and adventure genres, with Charles Dickens’ *Bleak House* (1853) employing it for legal searches. The phrase’s adoption was amplified in the 20th century through journalism and detective fiction, notably in Arthur Conan Doyle’s *Sherlock Holmes* stories, which celebrate thorough investigation. Its spread across English-speaking cultures was fueled by its universal appeal in problem-solving, ensuring its enduring use, from scientific research to personal quests.