immerˈsion noun

1. The act of immersing
2. The process or state of being immersed
3. Deep absorption or involvement
4. Baptism by immersing all or part of a person's body in water
5. The disappearance of a celestial body, eg in eclipse or occultation (astronomy)
6. A method of teaching a foreign language by giving the learner intensive practice in a situation in which all communication is in the language concerned
7. An immersion heater (informal)

immerˈsionism noun

immerˈsionist noun

A person who favours or practises baptism by immersion

immer'sive adjective

immersion foot noun

Another name for trench foot (see under trench)

immersion heater noun

An electrical apparatus directly immersed in the liquid, used for heating water

immersion lens noun

A microscope object-glass that works with a drop of oil or water between it and the cover glass