Meaning of IMMERSION in English

n.1 the act or an instance of immersing; the process of being immersed.

2 baptism by immersing the whole person in water.

3 mental absorption.

4 Astron. the disappearance of a celestial body behind another or in its shadow.

Phrases and idioms:

immersion heater an electric heater designed for direct immersion in a liquid to be heated, esp. as a fixture in a hot-water tank.

Etymology: ME f. LL immersio (as IMMERSE)

Oxford English vocab.      Оксфордский английский словарь.