1
general::
Phrase(s): (I) could(n’t) care less.
Inf. It doesn’t matter to me. (The less bears the heaviest stress in both versions. Despite the apparent contradiction, either reading of this—both the affirmative and negative—usually have the same meaning. The exception would be in a sentence where the could bears the heaviest stress: I COULD care less, [but I don’t.].) • Tom: The rain is coming! The carpet will get wet! Mary: I couldn’t care less. • Bill: I’m going to go in there and tell off the boss? John: I could care less., Phrase(s): could(n’t) care less
[one is] unable to care at all; it does not matter at all. • John couldn’t care less whether he goes to the party or not. • I could care less if I live or die.
McGrawhill's American Idioms And Phrasal Verbs