English Reference
noun

apparatus

n.
US /ˌæpɝˈætəs/ UK /ˌæpəɹˈeɪtəs/ ap·pa·ra·tus UK spelling apparatuses

  1. 01 C1 Advanced FormalTechnical Science

    the set of tools, machines, or instruments used for a particular job or scientific experiment.

    a collective term for the technical equipment or machinery needed for a particular activity or purpose.

    Simple

    The laboratory was filled with expensive apparatus for testing water quality.

    In context

    The researchers spent several weeks calibrating the delicate apparatus before they could begin the high-pressure chemical synthesis.

    Usage

    Usually treated as an uncountable or collective noun, though 'apparatuses' is the standard plural form.

  2. 02 C1 Advanced FormalAcademic

    the complex system of a government or organization that makes it work.

    the complex structure of a particular organisation or system, especially a political or bureaucratic one.

    Simple

    It is difficult to change the state apparatus because it has so many layers of rules.

    In context

    The party maintained control by embedding its loyalists deep within the administrative apparatus of the regional government.

  3. 03 B2 Upper Intermediate Sport

    the specific pieces of equipment that gymnasts use, like the bars or the rings.

    the various pieces of equipment on which gymnasts perform their exercises.

    Simple

    She practiced her routine on every apparatus, including the balance beam and the uneven bars.

    In context

    The gymnast moved fluidly from one apparatus to the next, demonstrating remarkable versatility across both the rings and the vault.

  4. 04 C2 Proficiency Technical Medicine

    a group of organs in the body that work together to do a job.

    a group of organs or structures that work together to perform a specific biological function.

    Simple

    The breathing apparatus in humans includes the lungs and the windpipe.

    In context

    Damage to the vestibular apparatus in the inner ear can lead to chronic issues with balance and spatial orientation.

Usage use apparatus

Counsel for the DPP claimed Judge Staines had fallen into fundamental error in interpreting a Supreme Court ruling that allowed motorists accused of drink-driving to inspect the relevant breath testing apparatus.

BreakingNews.ie· 14 Aug 2026

Under his rule, Syria’s fearsome security apparatus was given a free hand to arrest, torture and kill civilians on an industrial scale.

The Guardian· 11 Aug 2026

Etymology tree Proto-Indo-European *h₂éd Proto-Italic *ad Proto-Italic *ad- Latin ad- Proto-Indo-European *perh₃-der. Latin parō Latin apparō Proto-Indo-European *-tus Proto-Italic *-tus Latin -tus Latin apparātuslbor. English apparatus Learned borrowing from Latin apparātus. Doublet of apparat.

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

This entry
Level C1 · Advanced
Frequency Frequent
Updated