What is Bird Dog?

Legal Definition
A bird dog is a type of gun dog or hunting dog used to hunt or retrieve birds or other small game animals. by tracking their scent in the air. Bird dog breeds are receptive to being trained to retrieve hunted birds.

In the Southern United States the term bird dog refers to dog breeds such as the pointer, English setter, Red setter, German shorthair pointer, Nova Scotia Duck-Tolling Retriever, Brittany, and other pointing breeds.
-- Wikipedia
Legal Definition
An investor who searches but does not buy a property.