Treehouse
A treehouse was a structure built in a tree. In case of Humans, small treehouses were usually built for a child's amusement.

Rain Robinson's next-door neighbors had a treehouse that could be seen through her brother's telescope. She related this to a time traveling Tom Paris in 1996. ()

Aurelians residing on Starbase 25 lived in treehouses in the station's aviary. ()

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Architecture