Exercise, as influence

The answer to the crossword question “Exercise, as influence is WIELD” is the word “EXERT”. The clue suggests that the word that fits in the blank needs to mean the act of using physical or mental effort to achieve a result, and also have a similar meaning to the word “influence.” The word “wield” implies control or power, and “exert” means to apply or bring about something by using force, influence, or a particular quality. Thus, the answer fits perfectly well to the clue presented.