An addition, an extension.
An appendix to a book or document.
An addition or extension to a building.
An addition to the territory of a country or state, from a neighbouring country or state, normally by military force.
To add something to another thing, especially territory; to incorporate.
The ancient city of Petra was annexed by Rome.
To attach or connect, as a consequence, condition, etc.
to annex a penalty to a prohibition, or punishment to guilt
To join; to be united.