[singular] the greatest amount possible Our resources are strained to the utmost. He did his utmost (= tried as hard as possible) to persuade me not to go. Word Origin Old English ūt(e)mest ‘outermost’ (see out, -most).Extra examples He did his utmost to ensure his children’s happiness. She performed to the utmost of her abilities. The delays tried our patience to the utmost. The situation calls for the utmost in tact.