Lampreys are an order of jawless fish, the adult of which is characterized by a toothed, funnel-like sucking mouth. The common name "lamprey" is probably derived from Latin lampetra, which may mean "stone licker"

 

While lampreys are well known for those species which bore into the flesh of other fish to suck their blood, most species of lampreys are not parasitic and never feed on other fish.