The width of your thumb, if you need a rough approximation NYT crossword clue

The clue “The width of your thumb, if you need a rough approximation” points to an informal unit of measurement that’s been used for centuries. When people didn’t have rulers or tape measures handy, they would often estimate short lengths using parts of their body. The width of the thumb became a handy and consistent benchmark for rough approximations, especially in crafts or gardening.

The answer to this clue is “INCH.” While an inch is now precisely defined, its origin is tied to the approximate width of a human thumb. Historically, it was considered to be about the size of a man’s thumb at the base of the nail, and this practical association still makes the inch a relatable unit when estimating small distances without tools.