(2) - adj. - slang - Could get worse so as it is not so bad now;
(3) n and adj., used often by Americans who are sympathetic to the pro-nonsensical movement, modern-American Illiteratencia, and the Nouveau White Trash Riche.
The expression "I could not care less" originally meant 'it would be impossible for me to care less than I do because I do not care at all.'
Originally a British saying that came to the U.S. in the 1950s when the Republican Party was growing in popularity and strength across the nation.
By the 1980s, the GOP had achieved support from wide cross-sections of the American electorate, as it's policies of Educational eradication and cultural containment were attributable to economic growth, particularly strip-mall expansion and military weaponry for phantom enemies.
Language pro-incompetency became a primary political concern for the GOP, so long as it was butchered by "legal Americans," and with no strong ties to Mexican immigrants.
It became a simple, but memorable, issue for the GOP, surpassed only by the party's timeless rally call for more "Guns" and "God" and "less Gays."
While the now-common I could care less is senseless because If you could care less, that means you care at least a little.
The original is quite sarcastic and the other form is clearly nonsense.
Ex. # 1.
"I could not care less whether you lived or died! In fact, the only thing I care about less are splattered bugs on my windshield.!"
could care less gay republican apathy disinterest not care could care less give a fuck
"I could care less whether you lived or died. Before I knew that you really were my son, I could tell you were a homo-faggot, and I could care less or not have any fewer problems whatsoever with a person's right to kill gay people!"
Bob: Whatever. I could care less.