Is occasionally an adverb or pronoun?

The Word occasionally is an adverb, a Word that modifies a verb, an adjective, or another adverb. Examples:

I occasionally get a cold.

This is one of our occasionally hot Septembers.

A pronoun is a Word that takes the place of a noun in a sentence. Example:

Jim occasionally makes dinner himself. (the pronoun himself takes the place of the noun Jim)