In grammar, to modify is to change or add to the meaning of another word. A modifier is a word or group of words that does this. Adjectives modify nouns. Nouns can also be modified by other nouns and by prepositional phrases.In the examples that follow, the modifiers are printed in bold.Edgar Degas favoured his studio to the open (adjective) air, preferring to paint at the racecourse and in ballet (noun) studios. There was a smear of mud (prepositional phrase) on his nose. Adverbs modify adjectives.Isabella can very (adverb) easily come across as a prig. Modifiers that come before the word they modify are referred to as premodifiers:open air Those that follow the word they modify are postmodifiers:a smear of mud See also noun phrase, adjective phrase, adverb phrase.