~ is taught to people whose native language is not English but who live in a society in which English is the main language or one of the main languages. ~ is an abbreviation for ‘English as a second language’.
ESL
Meaning of ESL in English
Collins COBUILD. Толковый словарь английского языка для изучающих язык Коллинз COBUILD (международная база данных языков Бирмингемского университета) . 2012