1) Fish 2) Fish common name 
small parasitic Mediterranean fish
• (n.) A genus of small, slender fishes, remarkable for their habit of living as commensals in other animals. One species inhabits the gill cavity of the pearl oyster near Panama; another lives within an East Indian holothurian.
Fi`e·ras'fer noun [ New Latin ] (Zoology) A genus of small, slender fishes, remarkable for their habit of living as commensals in other animals. One species inhabits the gill cavity of the pearl oyster near Panama; another lives within an East Indian holothurian.