annex

American  

[uh-neks, an-eks, an-eks, -iks] / əˈnɛks, ˈæn ɛks, ˈæn ɛks, -ɪks /

verb (used with object)

1. to attach, append, or add, especially to something larger or more important.

2. to incorporate (territory) into the domain of a city, country, or state.

   Germany annexed part of Czechoslovakia.

3. to take or appropriate, especially without permission.

4. to attach as an attribute, condition, or consequence.

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noun

1. something annexed.

2. a subsidiary building or an addition to a building.

   The emergency room is in the annex of the main building.

3. something added to a document; appendix; supplement.

   an annex to a treaty.

annex British  

verb

1. to join or add, esp to something larger; attach

2. to add (territory) by conquest or occupation

3. to add or append as a condition, warranty, etc

4. to appropriate without permission

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noun

1. a variant spelling (esp US) of annexe

Other Word Forms

• annexable
  adjective
• nonannexable
  adjective
• preannex
  verb (used with object)
• reannex
  verb (used with object)
• unannexable
  adjective

Etymology

Origin of annex

First recorded in 1350–1400; (verb) Middle English, from Anglo-French, Old French annexer, from Medieval Latin annexāre, derivative of Latin annexus “tied to,” past participle of annectere ( see annectent); (noun) from French annexe or noun use of verb

Explanation

An annex is an extension of or an addition to a building. A small room off of a main room is an annex, and attics are another type of annex. As a noun, an annex is part of a building or an addition to a main structure, or it can be an attachment, as in "an annex to the current plans." When used as a verb, the word means something a little different. Sometimes annex is used as a nice word for "take" or "grab," as when Nazi Germany took the Sudetenland from Czechoslovakia in 1938 and added it to their own territory. In order to annex something to what is yours, you have to take it away from someone else.

Example Sentences

The lawsuit alleges that detainees face similar conditions as those at the annex, such as mold, disease, medical neglect and inadequate food and water.

From Los Angeles Times • May 21, 2026

Her vision is precise: a south-facing garden to catch the evening light, and a self-contained annex where her father might stay comfortably when visiting, or even live in later years.

From MarketWatch • Apr. 25, 2026

Among other changes, the Pentagon closed the correspondents’ corridor and said it would move credentialed journalists to a new workspace in an annex facility outside the building.

From The Wall Street Journal • Apr. 10, 2026

Frederiksen, 48, called the vote months earlier than expected, buoyed by popular support for her handling of US President Donald Trump's threat to annex Greenland, an autonomous Danish territory.

From BBC • Mar. 24, 2026

There was a new annex on the south side of the house, where younger women were filling bottles and packaging orders for shipment.

From "Educated" by Tara Westover

Related Words

• addendum
• appendix