The term 'Cousin of a Herring' can be solved by two crossword solutions: MENHADEN (8 letters) and SHAD (4 letters). MENHADEN are a type of fish found in the Atlantic and Gulf coasts of North America. They are an important food source for larger fish, marine mammals, and birds. SHAD are also a type of fish found in the Atlantic and Gulf coasts of North America. They are an important food source for larger fish, marine mammals, and birds, and are closely related to herring.