бързоходец

Noun

 * 1)  fast walker
 * 2)  old-time messenger, courier who travels on foot

Usage notes
In modern times, the word can sometimes be applied as a pseudonym of the roadrunner bird, due to the popular cartoon Wile E. Coyote and the Road Runner (translated in Bulgarian as “Бързоходеца и Уили Kойота”) which introduced the bird to Bulgarian audience.