English Reference
noun

immersion

n.
US /ˌɪˈmɝʒən/ UK /ɪmˈɜːʃən/ im·mer·sion UK spelling immersions

  1. 01 B2 Upper Intermediate

    the act of putting something completely under the surface of a liquid.

    the act of dipping or submerging something completely into a liquid.

    Simple

    The waterproof watch is designed for total immersion in water up to fifty metres.

    In context

    The process requires total immersion of the metal parts in a chemical bath to ensure the coating reaches every crevice.

    submergencedipping
  2. 02 B2 Upper Intermediate

    the state of being completely involved in something so that you do not notice anything else.

    the state of being deeply engaged or involved in an activity, environment, or interest.

    Simple

    His immersion in his work meant he often forgot to eat lunch.

    In context

    The virtual reality headset provides a level of immersion that makes players feel as though they are physically present in the game world.

  3. 03 B2 Upper Intermediate Academic Science

    a way of learning a language by only using that language for everything you do.

    a method of foreign-language instruction in which the target language is used as the sole medium of communication and instruction.

    Simple

    She spent the summer in a French immersion program to improve her speaking skills.

    In context

    Total immersion programs are often more effective than traditional classroom settings because they force students to navigate daily life in the target language.

  4. 04 B2 Upper Intermediate British EnglishInformal

    an electric device used to heat water in a tank.

    an electric water heater that is placed inside a water tank to heat the water directly.

    Simple

    Don't forget to turn off the immersion after you have your shower.

    In context

    The landlord promised to fix the immersion, as the tenants had been without hot water for three days.

    immersion heater
  5. 05 C2 Proficiency Technical Math

    a special way of matching points from one shape to another in math.

    a smooth map between manifolds whose differential is everywhere injective.

    Simple

    The professor explained how an immersion differs from an embedding in geometry.

    In context

    In differential topology, an immersion is a differentiable map between manifolds whose derivative is everywhere injective.

  6. 06 C2 Proficiency Technical Science

    when a star or planet disappears behind another object in space.

    the disappearance of a celestial body as it passes behind another or into its shadow.

    Simple

    The telescope captured the exact moment of the moon's immersion into the Earth's shadow.

    In context

    Astronomers calculated the precise timing of the immersion to better understand the satellite's orbital path.

    occultationeclipse
    emersion

In other areas, instructors may employ a deeper immersion into developing, using and evaluating AI tools.

Phys.org· 21 Aug 2026

From late Middle English, borrowed from Late Latin immersiō, immersiōnem (“dipping”).

Etymology adapted from Wiktionary, available under CC BY-SA 4.0.

This entry
Origin la-lat immersio
Level B2 · Upper Intermediate
Frequency Frequent
Updated