accession

A coming to; the act of acceding and becoming joined

“a king's accession to a confederacy”

Increase by something added; that which is added; augmentation from without.

A mode of acquiring property, by which the owner of a corporeal substance which receives an addition by growth, or by labor, has a right to the part or thing added, or the improvement (provided the thing is not changed into a different species).

The act by which one power becomes party to engagements already in force between other powers.

The act of coming to or reaching a throne, an office, or dignity.

The invasion, approach, or commencement of a disease; a fit or paroxysm.

Agreement.

Access; admittance.

To make a record of (additions to a collection).