English Reference
noun

HIV

n.
US /ˈeɪˈtʃaɪˈvi/ hiv

  1. 01 B2 Upper Intermediate Medicine

    Stands for Human Immunodeficiency Virus. This virus attacks the cells that help the body fight infections.

    Abbreviation for Human Immunodeficiency Virus. A lentivirus that causes HIV infection and over time acquired immunodeficiency syndrome (AIDS).

    Simple

    Modern medicine allows people living with HIV to lead long and healthy lives.

    In context

    Public health initiatives have focused on increasing access to testing and antiretroviral therapy to reduce the transmission of HIV within the community.

    Usage

    Usually used as an uncountable noun without an article when referring to the condition or virus generally.

    Teacher's tip

    Learners should distinguish between HIV (the virus) and AIDS (the late-stage syndrome caused by the virus).

  2. 02 C2 Proficiency Technical Science

    A special valve used in engineering to stop the flow of liquids or gases in a pipe.

    Abbreviation for Header, Helium, or Hydraulic Isolation Valve. A safety or maintenance component designed to stop the flow of process fluid in a piping system.

    Simple

    The technician checked the HIV to ensure no gas was leaking into the main chamber.

    In context

    During the pre-flight checklist, the engineers verified that the helium isolation valve (HIV) was responding correctly to the remote command.

    Usage

    In this technical sense, it is a countable noun and often takes an article.

    Teacher's tip

    This sense is highly specialized; unless teaching students in aerospace or fluid engineering, focus on the medical sense.

    shut off valve

Mercury had, in fact, tested positive, and six months later his doctors confirmed his HIV had progressed to Aids.

The Guardian· 1 Sept 2026
This entry
Level B2 · Upper Intermediate
Frequency Common
Updated