Someone who is bilingual can speak two languages equally well, usually because they learned both languages as a child.
He is bilingual in French and English.
bilingual in British English
(baɪˈlɪŋɡwəl)
adjective
1.
able to speak two languages, esp with fluency
2.
written or expressed in two languages
noun
3.
a bilingual person
Derived forms
bilingualism (biˈlingualˌism)
noun
bilingually (biˈlingually)
adverb
bilingual in American English
(baɪˈlɪŋgwəl)
adjective
1.
of or in two languages
2.
using or capable of using two languages, esp. with equal or nearly equal facility
3.
designating a method of education in which students who are not yet fluent in the language of the country where they live are taught in their native language