ENGLISH
REFERENCE

annex

v. · n.
US //ˈæˌnɛks// an·nex
  1. 1 to take territory (v.)
    C1 Advanced Formal Law

    to take control of another country's land and make it part of your own.

    to incorporate a territory into the domain of a city, country, or state, often without the consent of the original owner.

    Example

    The larger country decided to annex the small island after the war ended.

    Example

    The empire sought to annex the border provinces to secure its access to the northern trade routes and mineral deposits.

    Usage

    The verb is transitive and usually describes actions taken by governments or military forces.

  2. 2 extra building (n.)
    B2 Upper Intermediate

    an extra building that is joined to or used with a main building.

    a subsidiary building or an extension added to a main structure to provide additional space.

    Example

    The school built a new annex to provide more space for the science labs.

    Example

    The museum's modern annex houses the contemporary collection, providing a stark architectural contrast to the original nineteenth-century wing.

Show 1 more senseShow fewer
  1. 3 document appendix (n.)
    C1 Advanced Formal Academic Law

    an extra part added to the end of a report, book, or contract.

    an addition or appendix to a written document, such as a treaty, contract, or legislative bill.

    Example

    You can find the technical details in the annex at the back of the report.

    Example

    The specific environmental regulations are detailed in the third annex of the international trade agreement.

Etymology 1

Borrowed from French annexe, from Latin annexus. More at Etymology 2.

Etymology 2

From Middle English annexen, anexen, from Old French annexer (“to join”), from Medieval Latin annexāre, infinitive of annexō, frequentative of Latin annectō (“bind to”), from ad (“to”) + nectō (“tie, bind”). Compare the rare annect. Doublet of adnex.

Word family

© 2026 English Reference