Post"er (?), n.
1.
A large bill or placard intended to be posted in public places.
2.
One who posts bills; a billposter.
© Webster 1913.
Post"er, n.
1.
One who posts, or travels expeditiously; a courier.
"
Posters of the sea and land."
Shak.
2.
A post horse.
"
Posters at full gallop."
C. Lever.
© Webster 1913.