MONOLINGUAL

monolingual

(adjective) using or knowing only one language; “monolingual speakers”; “a monolingual dictionary”

monolingual

(noun) a person who knows only one language

Source: WordNet® 3.1

Etymology

Adjective

monolingual (comparative more monolingual, superlative most monolingual)

Knowing or using a single language; written or spoken in a single language.

Synonym: unilingual

Antonyms: multilingual, plurilingual

Noun

monolingual (plural monolinguals)

a person who knows or uses only a single language; a monoglot

Source: Wiktionary