I’ve encountered the term hidalgo in various contexts; it refers to Spanish or Portuguese nobility. The thing that surprised me about that term is the etymology: it’s from Old Spanish fijo dalgo, literally meaning “son of something.”
In the Spanish language of that period, in the phrase Hijo de algo, the word algo ("something") denotes "riches"[…]
…but like the other etymologies on that page, that claim about “something” specifically meaning “riches” is without attribution, so take that part with a grain of salt. But the fijo dalgo etymology is from MW11, so I trust that part.