A girl or woman who typifies or is the perfect example of a particular characteristic, attitude, opinion, cause, or type of person. Georgina managed to disassemble their washing machine, fix the problem, and then reassemble it all by herself? Wow, she's like the poster girl of DIY. What new earth-saving plan does the poster girl for environmentalism have in mind now? Ms. Walsh built her fortune from nothing, through her own tireless work and intense ambition. She really is the poster girl for the rags-to-riches American Dream.