Palafitte refers to house built on raised piles, sometimes called 'stilt houses.' Most of the ones I've seen are in areas prone to flooding and the bayou country of Louisiana. These houses can actually be built in the water rather than just on land that might be flood-prone. There are probably more houses rebuilt on stilts in the New Orleans area that was devastated by Hurricane Katrina than Louisiana ever had before.
As for using archaic or obscure words in my writing, I try to avoid it because I don't want to make readers search for a dictionary or wonder about a meaning while they're in the process of reading my work. If I wrote historical fiction, I would be more likely to use such words if they were in use during the relevant era; however, I don't write that genre.
I have a broad vocabulary due to nearly 7 decades of reading, so it's often a great temptation to use what my granddad called three-dollar words in my writing. I do my best to avoid that temptation for the sake of my readers. If I slip and put some in, they are usually the first things to be cut in my second draft. We don't write solely for our own enjoyment if we want readers. We must think of them and how they perceive the words on page or screen. Stopping to look up the meaning of a word (or even continuing to read while feeling puzzled about what the word meant) is a distraction for the reader. We should never do anything that will distract a reader from our fiction or non-fiction writing.