Most Helpful Girl
Definition of hunk: "a sexually attractive man, especially a large, strong one."
Definition of stud: "a guy; especially one who is virile and promiscuous." (a. k. a. a guy who's good with the ladies)
The technical definition of a jock is an athlete, but the stereotype of a jock is "muscular, but not very smart, and cannot carry a conversation on any topic other than one relating to sports, exercise, or sex."
So all three are sort of related to one another, but a hunk or a stud may not necessarily be into sports or exercise like a jock or be dumb like one. So a hunk or stud isn't always a jock, but a jock is typically a hunk or stud.