A person that is adverse to a wide variety of foods; additionally picky eaters often display an unwillingness to try new foods, or any food that contains even a small amount of a food they do not like.
Sally won't eat broccoli because she hates green vegetables she is such a picky eater. Bill won't eat that it has onions in it he is such a picky eater.
A person who doesn't eat a variety of pussy.
Chris is a picky eater, he only likes Chinese.