limpet (n.)

type of marine gastropod mollusk, early 14c., earlier lempet (early 14c.), alteration of Old English lempedu, which apparently originally meant "a lamprey" (both cling by sucking), from Medieval Latin lampreda "lamprey; limpet," from Late Latin lampetra "lamprey" (see lamprey). Limpin was a 16c. variant that survived in dialects.