peryton

noun2

1. •
   A fictional creature having the head and forelegs of a stag and the wings and hindquarters of a bird.

   • The peryton also makes an appearance, in a nod to its inventor, Borges — who compiled his own bestiary, “The Book of Imaginary Beings,” itself supposedly based on a long-lost medieval text. — 2007
2. •
   A radio signal which appears to come from outside the galaxy but is actually produced by terrestrial sources.

   • Three of these FRBs are factors of >3 narrower than any documented peryton. — 2013