Playa (Spanish for “beach”) comes from the Latin plaga, meaning “region to go hunting” (hunting for water animals, clearly!), which is related to the Greek plagos (“side” — the beach is just one side of your town!).
From that same root, we get the English Plagiarism — because the original Latin, in the sense of “hunting”, turned into “kidnapping”, which then turned into, “literary kidnapping.” Seriously!
The original Proto-Indo-European root, before it became Latin, for these words is *pele, meaning, “flat, spread out”. Think of the English, plain, as in, the plains of the midwest! And what is the beach of not flat land spread out? Well, most beaches, at least.