Why is a unicorn not a Unihorn?

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Tags

1. #unicorns
2. #greek
3. #comes
4. #which
5. #latin
6. #earlier
7. #horned
8. #literally
9. #pictures
10. #horses
11. #borrowed
12. #means
13. #cornu
14. #itself
15. #monoker
16. #unicorn