14-Letter Words Matching ____I_____O___

There are 20 14-letter words that match ____I_____O___. 4 are common words, such as ARCHIEPISCOPAL and COMMITTEEWOMAN. A rarer one is UREDINIOSPORES. In this set, A is the most frequent open letter (16 words). 2 words contain a doubled letter.

Full list 20

archiepiscopalcommitteewomancommitteewomensubmicroscopicunidirectionalamphiarthrosiscarcinomatosisspatiotemporaltachistoscopestherianthropictridimensionalbenzimidazolescarcinomatosesconfirmationalnondimensionalnondirectionalprecipitinogentachistoscopicunidimensionalurediniospores

About this list

Words
20 (4 common words)
Common example
archiepiscopal
Rare example
urediniospores
Doubled letters
2
Ending in S
6
Most frequent letter
A (16)

Questions

How many 14-letter words matching ____i_____o___ are there?

20. 4 of them are common words.

What is a common example?

ARCHIEPISCOPAL is among the common words in this set.