Boca Raton

From Bocaratone, from Boca Ratone Lagoon, from Spanish Boca de Ratones, from boca + ratone. Though named after Boca de Ratones, that region is actually in Biscayne Bay in Miami-Dade County, Florida, USA; not Palm Beach County. Later English cartographers replaced the Spanish location at Rio Seco (“Dry River”) with Boca Ratone Sounde, where a lagoon was located, now called Lake Boca Raton. The original Boca de Ratones on Biscayne Bay, was an inlet (“boca”) with a rocky bottom, that would grind (“ratonar”) mooring lines. The city of Boca Raton has a folk etymology, relating the name as "Rat's Mouth", where ratón (“mouse”) is mistaken for rata (“rat”), and boca is "mouth". This pertains to the local belief that the area hosted a pirate's lair (rats' lair), leading the city to have a pirate ship on the city seal (“coat of arms”).

来源：wiktionary