What are Tetrapods? (Tetrapods Resist Wave Impact and Prevent Beach Erosion)

Tetrapod means "four-legged" in Greek. In coastal engineering, tetrapods are star-shaped four-legged concrete structures placed on the beach to prevent erosion and reduce wave energy/impact. Love them or hate them, the name has become so famous that now even the three-egged concrete structures are also known as tetrapods.