“Derivative of sin” crossword clue

Reveal the answer to see why it works and where this clue has appeared before.COS is the answer to the New York Times crossword clue “Derivative of sin”. It was last seen in the puzzle of October 24, 2025, where it runs at 16 Down and fills 3 squares. It crosses 3 other entries in that grid — those are listed below and are the quickest way to confirm the letters you already have.