New wing of a building (5)
I believe the answer is:
annex
(Other definitions for annex that I've seen before include "Add to the end; take possession of" , "Addition to a document" , "Join - add" , "Take (land) by conquest" , "Seize" .)
I believe the answer is:
annex
(Other definitions for annex that I've seen before include "Add to the end; take possession of" , "Addition to a document" , "Join - add" , "Take (land) by conquest" , "Seize" .)