In English, Steve is my first cousin because he and I share a grandfather. Beth is my second cousin because she and I share a great grandfather.
I would assume that the Spanish term "primo" (= cousin) is a shortened form of the Spanish for first cousin, so that by analogy a second cousin would be called a "segundo." But it seems that actually a second cousin is called a "primo segundo," a second first.
Is that more logical than it seems? Can anyone share anything about the etymology of this nomenclature? Was there formerly another way of expressing these relationships that did not seem oxymoronic?