1. Someone who is a typical or quintessential example of something, or is used represents a particular cause or ideal
   "She became the poster child for environmental activism"
    
2. A child afflicted by some disease or deformity whose picture is used on posters to raise money for charitable purposes
   "she was the poster child for muscular dystrophy"

Derived forms: poster children

Type of: child, kid [informal], kiddie [informal], kiddy [informal], minor, nestling [informal], nipper [informal], shaver [informal], small fry [informal], tiddler [Brit, informal], tike [informal], tyke [informal], wean [UK, Ireland, dialect], youngster

Encyclopedia: Poster child