What is a fertilized duck or chicken egg boiled and eaten called?

A fertilized duck or chicken egg boiled and eaten is typically called a balut or penoy (in the Philippines).

Balut refers to a fertilized duck egg that has been incubated for about 14-21 days, allowing the embryo to develop significantly.

Penoy is a smaller version of balut, with the embryo having developed for a shorter period.

It's important to note that balut and penoy are considered delicacies in some cultures, but they might not be appealing to everyone due to the presence of the developing embryo.