Is there a system for creating words for ordinal numbers?

I'm not sure if "sequential" is the right word, but what is the system for creating a sequence of numbers like this:

  1. primary (as in 1st in choice or importance)
  2. secondary (as in 2nd in choice or importance)
  3. tertiary (as in 3rd in choice or importance)
  4. ???
  5. PROFIT

What would be the following words after "tertiary" if there are any?


  • quaternary (adjective): fourth in order or rank; belonging to the fourth order.
  • quinary (adjective): of or relating to the number five
  • senary (adjective, rare): relating to or based on the number six
  • septenary (adjective)
  • octonary (adjective, rare)
  • nonary (adjective, rare)
  • denary (adjective)

(source: New Oxford American Dictionary)


Ordinal numbers describes these sorts of sequential forms in general.

This refers to the common first, second, third… as well as to the latinate primary, secondary, tertiary, though, so may not be quite specific enough for you.