What does horseshoe crab mean?
• HORSESHOE CRAB (noun) The noun HORSESHOE CRAB has 1 sense: 1. large marine arthropod of the Atlantic coast of North America having a domed carapace that is shaped like a horseshoe and a stiff pointed tail; a living fossil related to the wood louse Familiarity information: HORSESHOE CRAB used as a noun is very rare.