Langostino can mean one of three things.
If you see this on a seafood menu, it could be one of three things. It is
Spanish for prawn. A prawn can be a shellfish that looks like a little
lobster, complete with tiny claws. They are sweet and delicate. In Florida, they are called “lobsterettes.” Prawn also means freshwater shrimp. And, finally, a prawn can be any large shrimp (15 or fewer per pound), also known as jumbo shrimp.
-- The Repository (Canton, Ohio)