Definition of railbird in US English:

railbird

noun

North American
informal
  • A spectator, especially one at a horse race who watches from the railings along the track.

    • ‘People who might not have come to the track are attracted by slot bonanzas, and die-hard rail birds are spending more money.’

Pronunciation

railbird

/ˈreɪlbərd//ˈrālbərd/