1620s, from Medieval Latin annexiationem (nominative annexatio) "action of annexing," noun of action from past participle stem of annexare (see annex). The Middle English noun form was annex [..]

Annexation is the forced acquisition of a region or territory by a more powerful state, such as Austria-Hungary’s annexation of Bosnia in 1908.

Definition The process whereby a city expands its boundaries to include a specific geographic area. Most states require a public vote be held within the city and the area to be annexed in order to det [..]

In the law relating to fixtures, annexation is actual or constructive. Actual annexation means every movement by which a chattel can be joined or united to the freehold. Constructive annexation means [..]

(n) incorporation by joining or uniting(n) the formal act of acquiring something (especially territory) by conquest or occupation

This is the process of adding or incorporating an area into a city's jurisdiction.

Permanently incorporating real property, (i.e., such as a city adding additional land to increase its size).