blue crab

noun5

1. •
   Any member of either of two groups of crab
2. •
   Any crab of genus Callinectes
3. •
   especially of species Callinectes sapidus of eastern US
4. •
   A crab of species Portunus pelagicus
5. •
   Any of several species of crab with three-part vernacular names. (See Derived terms and Related terms below.)