Using or able to use two languages, especially with equal or nearly equal fluency.
Using two languages in some proportion in order to facilitate learning by students who have a native proficiency in one language and are acquiring proficiency in the other: bilingual training; bilingual education.
Of, relating to, or expressed in two languages: a bilingual dictionary.
n. A person who uses or is able to use two languages, especially with equal fluency. bi·lin'gual·ism n., bi·lin'gual·ly adv.