The answer to the NYT crossword clue "Ad ___" that appeared in the October 2, 2025 puzzle is "HOMM" (4 letters) according to recent crossword solution sources. This answer specifically corresponds to the clue "Ad ___" as used in that edition of the New York Times crossword puzzle.

If a clue "Ad ___" appears in other contexts or with different letter counts, it may have other possible answers such as "LIB," "HOC," "REP," "PLUG," or "BILL" among others, but for the NYT puzzle and date mentioned, "HOMM" is the precise solution.