Meaning of IMMERSION in English

■ noun

1》 the action of immersing or the state of being immersed.

2》 a method of teaching a foreign language by the exclusive use of that language.

3》 Astronomy the disappearance of a celestial body in the shadow of or behind another.

Concise Oxford English vocab.      Сжатый оксфордский словарь английского языка.