1. having a hard outer shell or crust
2. of or relating to crustaceans (such as crabs, lobsters, and shrimp)
Usage: zoological

Examples

• The crustaceous lobster had a tough, protective shell.
• Marine biologists study various crustaceous species in the ocean.
• The crab’s crustaceous exterior protected it from predators.
• Crustaceous animals molt their shells as they grow.
• The restaurant specialized in crustaceous seafood dishes.
• Scientists examined the crustaceous fossils found in the limestone.