poster in WordNet English dictionary

1. a sign posted in a public place as an advertisement
   "a poster advertised the coming attractions"
   poster  posting  placard  notice  bill  card 
   
2. someone who pastes up bills or placards on walls or billboards
   bill poster  poster  bill sticker 
   
3. a horse kept at an inn or post house for use by mail carriers or for rent to travelers
   post horse  post-horse  poster