adverb

n. part of speech used to modify verbs adjectives and other adverbs (Grammar)

An adverb is a part of speech. It is any word that modifies any other part of language: verbs, adjectives (including numbers), clauses, sentences and other adverbs, except for nouns; modifiers of nouns are primarily determiners and adjectives.Adverbs typically answer such questions as how?, when?, where?, to what extent?, in what kind? or how often? This function is called the adverbial function, and is realized not just by single words (i.e., adverbs) but by adverbial phrases and adverbial clauses. Adverbs also describe adjectives, verbs, and other adverbs.
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Noun
1. the word class that qualifies verbs or clauses
(hypernym) major form class
2. a word that modifies something other than a noun
(hypernym) modifier, qualifier
(hyponym) adverbial

n. adverb, part of speech used to modify verbs adjectives and other adverbs (Grammar)

(n.)
A word used to modify the sense of a verb, participle, adjective, or other adverb, and usually placed near it; as, he writes well; paper extremely white.