15-Letter Words Matching ___________NA__

There are 17 15-letter words that match ___________NA__. 4 are common words, such as CARDIOPULMONARY and CONSTITUTIONALS. A rarer one is UNREVOLUTIONARY. In this set, I is the most frequent open letter (16 words). 4 words contain a doubled letter.

Full list 17

cardiopulmonaryconstitutionalsnondisciplinarynoninflationaryinsurrectionarymetropolitanatesesquicarbonatetransilluminateunproportionatedisinflationaryquatercentenarysesquicentenarysubstitutionaryuncompassionateunextraordinaryunprofessionalsunrevolutionary

About this list

Words
17 (4 common words)
Common example
cardiopulmonary
Rare example
unrevolutionary
Doubled letters
4
Ending in S
2
Most frequent letter
I (16)

Questions

How many 15-letter words matching ___________na__ are there?

17. 4 of them are common words.

What is a common example?

CARDIOPULMONARY is among the common words in this set.