The literal translation of "Boca Raton" is "Mouse Mouth" ("mouse" in Spanish is "ratón"). One explanation for the origin is the Spanish word boca (or mouth) was (and still is) used to describe an inlet and ratón (literally "mouse") was used by Spanish sailors to describe rocks that gnawed at a ship's cable. Another explanation is that it refers metaphorically to the sense of pirate's cove. The name Boca Ratones originally appeared on eighteenth century maps associated with an inlet in the Biscayne Bay area of Miami. By the beginning of the nineteenth century, the term was mistakenly moved north to its current location on most maps and applied to the inland waterway from the closed inlet north for 8.5 miles (13.7 km), which was called the "Boca Ratones."