Annexe

A framed tent structure which can be attached to a motorhome and left as a free-standing unit in its own right if you drive away
Found on http://www.encyclo.co.uk/local/20699

Annexe

An annexe or annex is an extension to a main building. Typically an additional room constructed after the main building has been completed. In America and Canada an annexe is also known as an addition.
Found on http://www.probertencyclopaedia.com/browse/TA.HTM
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