The term "bulldog" has several meanings depending on its context.
1) In a general sense, bulldog refers to a breed of dog known for their stocky build and wrinkly face. They are typically friendly, loyal, and make great family pets.
2) Bulldog can also refer to someone who is tough or stubborn, with an unwavering determination to achieve a goal despite obstacles or opposition. This usage often implies that the person has a strong will and courage in facing challenges.
3) In sports, particularly basketball, "bulldog" is used as a term of encouragement for a player who shows great hustle, tenacity, and determination on the court.