accession

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.

verb (used with object)

9. to make a record of (a book, painting, etc.) in the order of acquisition.
10. to acquire (a book, painting, etc.), especially for a permanent collection.

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 (def. 2)

verb

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

n.

“act of coming to a position,” especially of a throne, 1640s, from Latin accessionem (nominative accessio) “a going to, joining, increase,” noun of action from past participle stem of accedere (see accede).