A grammatical category that modifies verbs, adjectives, or other adverbs by providing additional information about manner, degree, frequency, or time, without functioning as a subject or predicate.

A class of words that are independent and do not change form, primarily used to enhance the meaning of other words, often segmentable into various types such as state, degree, and declarative adverbs.

A part of speech characterized by its ability to provide context to actions or qualities, typically expressing how, when, or to what extent something occurs, without acting as a standalone sentence element.