What do you call a word that describes an adverb?

There isn't a specific word for a word that describes an adverb.

Here's why:

* Adverbs are already described by their function: They modify verbs, adjectives, or other adverbs.

* Describing adverbs focuses on their meaning: We might talk about an adverb's degree (e.g., "very" or "somewhat"), its manner (e.g., "quickly" or "carefully"), or its time (e.g., "now" or "later").

Instead of a single word, we use phrases like:

* Adverbial modifier

* Descriptive term for an adverb

* Word that tells us more about the adverb

Let me know if you have any other questions!