Most language I have some knowledge of have adjectives with are either a) nominal in nature or b) verbal in nature. (apologies if this is not the best wording.)
- In German, Romanian, and Georgian, adjectives decline for noun properties such as case.
- In Japanese and Korean, most adjectives inflect like verbs. In Chinese there is no inflection but adjectives are described as incorporating the verb "to be".
So obviously there are always various features that make adjectives behave a bit differently from nouns or verbs, but are there languages where adjectives are morphosyntactically a very distinct category that cannot be related to either nouns or verbs?
Maybe this question only makes sense for inflecting languages since the syntax seems to vary for all three and in languages with little inflection like English where there is not much inflection difference even between nouns and verbs.