could care less

Meaning

Verb

• To not care at all; to have no concern or interest; to be apathetic.

Origin

• An alteration of couldn't care less (which is first attested slightly earlier), either:
• by deliberate irony, or
• by erroneous hyponegation, perhaps influenced by forms such as “as if I could care less”, “no one could care less”, and “to know little (or nothing) and care less”.