The plural of bureau is bureaus or bureaux.
A bureau is a piece of furniture or an organizational unit that provides storage, workspace, or administrative functions. It typically consists of drawers, shelves, and a flat writing surface. Bureaus can be used in various settings, such as offices, homes, and government institutions, to store documents, stationery, and other items. In a broader context, a bureau can also refer to a department or division within an organization or government that performs specific tasks or provides services. The term 'bureau' is often associated with professionalism, organization, and efficiency.
The graph shows the occurances of the plural of bureau in written English since 1800 using Google's Ngram Viewer.
Sources: