Something that's recherche is very fancy, and maybe a little bit rare. Taking an elegant ocean liner from New York to France would be a recherche way to travel.
Language can be recherche, when it's especially complicated. If you're writing a story and instead of "She said," you write "She opined" or "She emoted," your style is fairly recherche. And if everyone at a party is wearing jeans, but you wear a tuxedo, your outfit is recherche. In French, recherché means "carefully sought out," from chercher, "to search."