Yellow dog is a term often used to describe a mongrel or mixed breed dog that has yellow or tan fur. However, there are many synonyms for this term that can be used to describe a dog with similar physical attributes or characteristics. Some examples include "mutt," "cur," "street dog," "stray," and "crossbreed." These terms emphasize the dog's mixed heritage and often imply that the dog may not have a specific breed lineage. Other synonyms that focus on the dog's color could include "blonde," "fawn," "ginger," or "brassy." Ultimately, the term used to describe a yellow dog will depend on the specific context and the traits the speaker wishes to emphasize.