Definition of "zeedonk"

Tigons, ligers and a zeedonk have also been created by miscegenating mammals.

1985, Hartson & Dawson, The Ultimate Irrelevant Encyclopedia, page 66

One might have imagined that it could only have been Dr. Seuss who had thought up and named the zedonk—the animal produced when a male zebra mates with a female donkey!

1997, Thomas Fensch, Of Sneetches and Whos and the Good Dr. Seuss

Suggest which animals are the parents of the cross breeds, zedonk and tiglion.

2003, Colin Bell, GCSE Applied Science Student Book

I could have told him about zedonks and zebrasses; donkey cures for whooping cough and gout, how an onager is a wild ass from Central Asia; that the Australian kookaburra is nicknamed “the laughing donkey”; [...]

2004, Kevin O'Hara, Last of the Donkey Pilgrims