Egg

1. The oval or roundish body laid by domestic poultry and other birds, tortoises, etc. It consists of a yolk, usually surrounded by the "white" or albumen, and inclosed in a shell or strong membrane.
2. To urge on; to instigate; to incite/
3. Anything resembling an egg in form.
4. A simple cell, from the development of which the young of animals are formed; ovum; germ cell.