1.a process of increasing by addition (as to a collection or group);
the art collectin grew through accession
2.(civil law) the right to all of that which your property produces whether by growth or improvement
3.something added to what you already have;
the librarian shelved the new accessions
4.agreeing with or consenting to (often unwillingly);
accession to such demands would set a dangerous precedent
5.the right to enter
6.the act of attaining or gaining access to a new office or right or position (especially the throne);
Elizabeth's accession in 1558
1.make a record of additions to a collection, such as a library