Noun
a domestic hen ready to brood
Source: WordNetbroody-hen
A Royal Commission is a broody hen sitting on a china egg. Michael Foot
When I was a small boy, following the affairs of the House of Commons as closely as I could, I asked my father what a Royal Commission was. He said, "It is a broody hen sitting on a china egg." Michael Foot
Most domestic ducks neglect their eggs and ducklings, and their eggs must be hatched under a broody hen or artificially. Source: Internet
The broody hen will stop laying and instead will focus on the incubation of the eggs (a full clutch is usually about 12 eggs). Source: Internet