(as|) sharp as a tack
1
(of a person) having or showing a high level of intelligence
The phrase "sharp as a tack" is believed to have originated in the United States, likely in the early to mid-20th century. The phrase draws upon the sharpness of a tack, which is a small pointed nail used for securing objects. This idiom is used to emphasize someone's intelligence, mental acuity, and quick thinking. It conveys a sense of admiration for their sharpness of mind and intellectual prowess.
- Don't underestimate him.He's as sharp as a tack and always comes up with innovative solutions.
- Even at her age, she's still sharp as a tack.Her memory and cognitive abilities are remarkable.
- He's a brilliant student, sharp as a tack in every subject he studies.
- She's a formidable debater, always quick with her responses and sharp as a tack in her arguments.
- The detective's mind is sharp as a tack.She can quickly piece together clues and solve complex cases.