I visited my friend Duncan last week at his parent’s house in Cold Spring Harbor, Long Island:
I learned this word from Duncan’s mother, Elizabeth Watson, an architectural historian. She has a these good examples of simple, utilitarian portière in her own house:
This architectural term comes from the French word for door, porte. Common in wealthier households during the Victorian era (according to Wikipedia,) curtains are still a great way to create privacy, mitigate drafts, hide a messy closet, subdivide a space, or create a cozy nook. Its much more affordable to put up a curtain than install any sort of door, and it is especially appropriate if you need a temporary or quick solution, or if you get excited about fabrics or a splash of color.
Here is a fancier example of Portière from the National Gallery in Washington DC:
I also found this drapery design blog with all sorts of examples of portière.