Here is a medical distinction between "Guts" and "Balls", according to the British military. We've heard colleagues referring to people with "Guts", or with "Balls". Do they, however, know the difference between them? Here's the official distinction; straight from the British Medical Journal: Volume 323; page 295. GUTS - Is arriving home late, after a night out with the lads, being met by your wife with a broom, and having the "Guts" to ask: "Are you still cleaning, or are you flying somewhere?" BALLS - Is coming home late after a night out with the lads, smelling of perfume and beer, lipstick on your collar, slapping your wife on the bum and having the "Balls" to say: 'You're next, Chubby.' I trust this clears up any confusion. Medically speaking, there is no difference in outcome; both are fatal.