What term describes a derogatory comment impacting a person's reputation?

The term that best describes a derogatory comment that negatively affects a person's reputation is "detraction." Detraction refers specifically to the action of taking away from the worth or reputation of someone or something through critical remarks. It implies a form of disparagement that can lead to a loss of esteem or credibility. When someone detracts from another person, they often make unfounded or exaggerated claims that could harm that person’s image in the eyes of others.

In contrast, the other terms do not directly relate to derogatory comments impacting reputation. A deterrent usually refers to something that discourages an action, while a distraction is something that diverts attention away from the current focus. Derision involves mocking or scorn, which, while related, does not specifically capture the broader context of reputation damage that detraction does. Therefore, detraction is the most fitting choice for this particular context.