I can’t think of any except strict antonyms where removing the prefix doesn’t leave you with a usable opposite word. Ex. intact where tact doesn’t mean broken into pieces.
I think that any adjective has an opposite by adding a not to the beginning or just changing part of the word (like the prefix or suffix). So to the best of my mere knowledge, I don’t think there is one.
What about numbers? I suppose those have no direct/definite opposites.
Well, @dxs, by your language logic, which is fine (thirsty——not thirsty), I would postulate that any number’s opposite is simply adding a + or – in front of it.
@Sunny2 I think that that counts as an opposite. @Blueroses I was figuring that, but I don’t know if that is completely true. it’s really late and I am too tired to do much, sorry :(
I think that everything has to have an opposite because without an opposite, there is nothing to compare to; it couldn’t be defined. Without evil there is no good; without Satan there is no God.
Nine as in nine days. Or do numbers that modify have a different name than adjective?
@dsx I still think colors qualify. Black and white are opposites, but colors don’t have opposites. I think you can put an ‘un’ or non’ in front of a lot of adjectives and it is a challenge to find adjectives that do not have opposites.