the.com/annexation

means The formal act of a state claiming sovereignty over territory and folding it into its own, usually without asking the people who already live there.

from From Latin annexare, 'to bind to' — ad ('to') plus nectere ('to tie, to bind'), the same root that gives us 'connect.' Originally just the neutral verb for attaching one thing to another, like tying a document to a contract. Its political sense — one state tying a piece of land permanently to itself — hardened into legal and diplomatic use by the 18th and 19th centuries, as empires needed a tidy word for what conquest looked like once lawyers got involved.