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A description of an optical system whose image plane is bounded by a liquid in order to raise the numerical aperture, as in lithography and microscopy;

A baptism where the entire body is placed below water;

Language immersion;

A smooth map whose differential is everywhere injective, related to the mathematical concept of an embedding;

Telepresence;

The Immersion Corporation, a haptic technology developer;

An immersion heater, a kind of water heater;

360° immersive video.