1. primary
2. secondary
3. tertiary
4. quaternary
5. quinary
6. senary
7. septenary
8. octonary
9. nonary
10. denary
11. (none)
12. duodenary
13. (none)
14. (none)
15. (none)
16. (none)
17. (none)
18. (none)
19. (none)
20. vigenary

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There are no sequential words following: once, twice, and thrice

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Whereas misogynist is a person who hates or dislikes females, misandrist is a person who hates or dislikes males.

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Diurnal is the opposite of nocturnal.

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Angry and hungry are the only two words that end with gry.

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Sororal is the female equivalent of fraternal.

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Nothing rhymes with orange or silver.

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