accession

American  

[ak-sesh-uhn] / ækˈsɛʃ ən /

noun

1. the act of coming into the possession of a right, title, office, etc..

   accession to the throne.

2. an increase by something added.

   an accession of territory.

3. something added.

   a list of accessions to the college library.

4. Law. addition to property by growth or improvement.

5. consent; agreement; approval.

   accession to a demand.

6. International Law. formal acceptance of a treaty, international convention, or other agreement between states.

7. the act of coming near; approach.

8. an attack or onset, as of a disease.

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verb (used with object)

1. to make a record of (a book, painting, etc.) in the order of acquisition.

2. to acquire (a book, painting, etc.), especially for a permanent collection.

accession British  

/ əkˈsɛʃən /

noun

1. the act of entering upon or attaining to an office, right, condition, etc

2. an increase due to an addition

3. an addition, as to a collection

4. property law

   1. an addition to land or property by natural increase or improvement

   2. the owner's right to the increased value of such land

5. international law the formal acceptance of a convention or treaty

6. agreement; consent

7. a less common word for access

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verb

1. (tr) to make a record of (additions to a collection)

Other Word Forms

• nonaccession
  noun
• reaccession
  noun
• accessional
  adjective
• unaccessional
  adjective

Etymology

Origin of accession

1580–90; < Latin accessiōn- (stem of accessiō ) an approach, addition. See access, -ion

Explanation

Accession is the act of advancing into a position. Being elected class president is a kind of accession. Accession originally referred to a queen or king taking the throne. From the Latin term, accessionem, meaning "joining or increasing,” accession may refer to the gaining of access to any formal position, group, or right. It can also mean “agreement” — think of it as “joining in.” Accession may also refer to property — either something that increases your original collection, or the right to all of your property even through growth — such as the golden egg your new hen laid.

Example Sentences

See Examples For:

accession

On Saturday, voters will be asked to answer "Yes" or "No" to the question: "Should Iceland resume accession negotiations with the European Union?"

From Barron's ● Aug. 26, 2026

It warned of a possible wave of arrivals on the occasion of Throne Day, which marks the anniversary of King Mohammed VI’s accession to the throne.

From The Wall Street Journal ● Aug. 9, 2026

His government quickly joined the North Atlantic Treaty Organization and expedited accession to the European Union.

From The Wall Street Journal ● Jul. 6, 2026

They suggested that prospective cabinet ministers and advisers could be picked before then and put through "accession talks" in August to better prepare them for government.

From BBC ● Jun. 22, 2026

The Saxons and Normans of Arthur’s accession had begun to think of themselves as Englishmen.

From "The Once and Future King" by T. H. White

Related Words

• enlargement
• extension