Answer: STOLENBASE

A stolen base is a term used in baseball. It refers to a base runner successfully advancing to the next base (usually from first to second base) without the batter actually hitting the ball. It is called a "diamond theft" because it involves the base runner attempting to advance to another base while the defense is focused on preventing them from doing so.

Note: The provided meaning of the answer is for the latest New York Times crossword puzzle clue: Diamond theft. Explanations are generated by AI and may be inaccurate.