Monolingual – the use of a single language.
Bilingual - The proficient use of two or more languages.
Simultaneous Bilingual – an individual that has learned two languages at the same time – usually since birth.
Sequential Bilingual - an individual that has learned one language and then a second or third language after three years of age.
Proficiency – the level of accuracy and fluency with which one is able to speak any acquired language.
Source Language - the original language of a document, piece of text or dialogue. The mother-tongue of a language learner.
Target Language – the language into which the source language is to be interpreted or translated. The foreign language a language learner is aiming to learn.
Interpreter – an individual trained in instantaneous oral translation from one source language to another target language.
Translator – an individual trained in written translation from one source language to another target language.
CEFR – Common European Framework of Reference for Language. The European standard assessment of language capability. CEFR stages include: A1 (Break-through), A2 (Waystage), B1 (Threshold), B2 (Vantage), C1 (Effective Operational Proficiency) and C2 (Mastery).
Dual Language Book – a book that offers simultaneous exposure to both the source and target language with the source language on one page and the target language on the opposite page. Also know as parallel text books.
We often use terms such as dual language books to refer to bilingual books and multicultural books for learning foreign languages.