Innuendo (or insinuation) is a rhetorical tactic often used to disguise other fallacies, such as ad hominem attacks; instead of directly denigrating a target, the arguer uses an allusion or other indirect statement to suggest that the target's character or circumstances are bad or compromised. One possible motive for doing so is that if the move is called out, the arguer can try to "back off" the innuendo, claiming they "didn't mean it" as a definitive accusation.

Here is an example:

Two college students are discussing the upcoming student elections at their school.

Mia: Why don't you think Alex should be Senior Class President?

Bart: Let me just say that if you ask his ex-girlfriends, they won't tell you he's a saint.

Bart is not outright attacking Alex's character, and we don't know what the "ex-girlfriends" would say, but the suggestion is that they would cast aspersions on Alex that would disqualify him (at least in Bart's view). This indirect, unspecified insult is a use of innuendo to dress up an ad hominem attack on Alex.

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