- The act of immersing or the condition of being immersed.
- The total submerging of a person in water as an act of baptism.
- (Britain, Ireland, informal) An immersion heater.
- (mathematics) A smooth map whose differential is everywhere injective, related to the mathematical concept of an embedding.
- (astronomy) The disappearance of a celestial body, by passing either behind another, as in the occultation of a star, or into its shadow, as in the eclipse of a satellite; opposed to emersion.
- (linguistics) A form of foreign-language teaching where the language is used intensively to teach other subjects to a student.
the act of immersing or the condition of being immersed
the total submerging of a person in water as an act of baptism