Make this text less complex: Sphyrna is one of the two genera in the Hammerhead shark group, and is the largest genera out of the two, with eight members in it. <SEP> The word " Sphyrna " is a Greek word meaning " hammer ", which refers to the shape of the shark's head.
Sphyrna (from the Greek word " σφυρι ́ " " hammer ") is a genus of hammerhead sharks with a cosmopolitan distribution in the world's oceans.