The boreyne is a monster vaguely similar to a bull, but with a horse’s mane, a lion’s forelegs and tail, an eagle’s hindlegs – to which are added curled horns, spear-headed tongue, and a fin spouting from its crupper. It was used as a canting badge by Borough (or Burgh) c.1466 [Dennys 152]. The boreyne does not seem to have a default posture; the illustration shows a boreyne passant.
Iago of Winged Hills bears as a badge: Or, a boreyne passant to sinister gules.