Why is British flag called Union Jack?

Related questions

1. Why should a flag never touch the ground?
2. Is wearing a flag disrespectful?
3. What is the symbolism of an upside down flag?
4. Does Great Britain have a flag?
5. Why does Great Britain have a flag?
6. Why is UK famous?
7. Is it illegal to throw away a flag?
8. What happens if a flag touches the ground?
9. What is unique about the UK?
10. What is nationality British or English?

Tags

1. #never
2. #already
3. #referred
4. #amended
5. #incorporate
6. #wondering
7. #incorporated
8. #ireland
9. #british
10. #patrick
11. #because
12. #england
13. #welsh
14. #principality
15. #union
16. #cross