Definition of "Emperor"

As military attaché to the British Embassy in Berlin he enjoyed the esteem of Emperors William and Frederick.

1902, The Outlook, page 701

Certainly LH levels rise in female Emperors during the brooding (guard) phase of chick rearing and decrease significantly in females that have lost their chicks, suggesting that there is a link between brooding behaviour and elevated LH levels.

2010, Lloyd Spencer Davis, Martin Renner, Penguins, page 128

Most Emperor breeding failures are actually caused by their fellow penguins: either a mate's careless transfer of the egg, or when a disgruntled neighbor's aggressive action slides or breaks the egg.

2011, David Salomon, Penguin-Pedia, page 29

There are Seventeen kinds of penguin, but the Emperor is the only one that breeds in Antarctica in midwinter.

2014, Martin Jenkins, The Emperor's Egg, page 3

Nevertheless the Emperors were unsettled owing, there can be no doubt, to the knowledge that bad weather was impending.

2016, Apsley Cherry-Garrard, The Worst Journey in the World: Antarctic 1910-1913