left-handed compliment (also, backhanded compliment)

noun-phrase

- a remark that seems to say something pleasant about a person but could also be an insult

Cambridge Dictionary

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It's probably politically incorrect, but almost everything is these days, and so many people are ready to take offense at so much that the word offensive is as meaningless to me as fascist (which actually refers to a person who supports a specific political system) and racist (How is it possible to be "racist" against women/Muslims/Brazilians/etc. when they aren't a "race"?) etc. You can us "backhanded" instead of "left-handed" if you're worried about offending lefties.

-This expression uses left-handed in the sense of "questionable or doubtful," a usage dating from about 1600.

Source: The American Heritage® Dictionary of Idioms by Christine Ammer.

For example, "She said my presentation was really great, only half the audience were asleep."



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say something like:

"I never know whether to believe him. Whenever he gives praise, it sounds like a left-handed compliment."