annex >> /əˈnɛks/
Definition: [transitive verb] Append or add as an extra or subordinate part, especially to a document.
Example: the first ten amendments were annexed to the Constitution in 1791
Definition: [noun] A building joined to or associated with a main building, providing additional space or accommodations.
Example: the school's one-story wooden annex
Definition: [noun] An addition to a document.
Example: an annex to the report