General:
* Descriptive
* Modifying
* Qualifying
* Attributive
* Predicative
* Characterizing
* Specifying
* Defining
* Coloring
More specific:
* Comparative (e.g., bigger, smaller)
* Superlative (e.g., biggest, smallest)
* Positive (e.g., big, small)
* Gradable (can be modified with adverbs like "very" or "quite")
* Non-gradable (cannot be modified with adverbs like "very" or "quite")
* Concrete (referring to tangible things)
* Abstract (referring to intangible ideas or concepts)
* Subjective (based on opinion)
* Objective (based on fact)
* Simple (one word)
* Compound (two or more words)
Other useful terms:
* Adjective phrase - a group of words that acts as an adjective (e.g., "very happy")
* Adjective clause - a dependent clause that modifies a noun (e.g., "the man who lives next door")
Ultimately, the best word to describe an adjective depends on the specific context.