15-Letter Words Matching _____O________N

There are 14 15-letter words that match _____O________N. 3 are common words, such as INSUBORDINATION and PROGNOSTICATION. A rarer one is PSYCHOHISTORIAN. In this set, I is the most frequent open letter (14 words). 5 words contain a doubled letter.

Full list 14

insubordinationprognosticationreincorporationautocorrelationcrossopterygianheterochromatinpsychometricianreafforestationhematoporphyrinimmunodiffusionmegacorporationoverconsumptionpostpollinationpsychohistorian

About this list

Words
14 (3 common words)
Common example
insubordination
Rare example
psychohistorian
Doubled letters
5
Ending in S
0
Most frequent letter
I (14)

Questions

How many 15-letter words matching _____o________n are there?

14. 3 of them are common words.

What is a common example?

INSUBORDINATION is among the common words in this set.