A possessed chicken. Typically a male chicken (rooster) which bears an overly aggressive nature, raises hackles without provocation, and looks at you cockeyed before his attack. May also apply to a person with the temperament of Barney Fife when overly excited or scared.
That poor sod is so upset, I swear he's a poultrygeist. The cock was so wacked out, it must be a poultrygeist.
The spirit of Thanksgiving past.
The poultrygeist of old home movies.