Why do people call McDonalds Mickey D's?

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Tags

1. #originally
2. #started
3. #first
4. #initial
5. #playful
6. #mcdonald
7. #someone
8. #syllable
9. #mickey
10. #people
11. #comes
12. #second
13. #spread
14. #heard
15. #calling
16. #version
17. #liked
18. #mcdonalds