monolingual

English Thesaurus

1. a person who knows only one language (noun.person)

hypernym	:	individual, mortal, person, somebody, someone, soul,
definition	:	a human being (noun.tops)

2. using or knowing only one language (adj.all)

antonym	:	multilingual,
definition	:	using or knowing more than one language (adj.all)

antonym	:	multilingual,
definition	:	using or knowing more than one language (adj.all)