Definitions

1. noun

The green bone-like structure found at the base of the beak in birds, particularly in waterfowl.

“The waterfowl’s unique greenbone helps it to dive and swim more efficiently.”

2. noun

A hard, greenish-colored bone in the beak of some birds, especially waterfowl.

“The green bone in the beak of this waterfowl species is a crucial adaptation for its aquatic lifestyle.”