15-Letter Words Matching __O_R__________

There are 13 15-letter words that match __O_R__________. 5 are common words, such as PROCRASTINATING and PROCRASTINATION. A rarer one is PROGRESSIVISTIC. In this set, I is the most frequent open letter (13 words). 5 words contain a doubled letter.

Full list 13

procrastinatingprocrastinationprocrastinatorsprogressivenessproprietorshipsneoarsphenamineprocrastinatoryprogrammabilityprogressivitiesproprietoriallyproprioceptionsexoerythrocyticprogressivistic

About this list

Words
13 (5 common words)
Common example
procrastinating
Rare example
progressivistic
Doubled letters
5
Ending in S
5
Most frequent letter
I (13)

Questions

How many 15-letter words matching __o_r__________ are there?

13. 5 of them are common words.

What is a common example?

PROCRASTINATING is among the common words in this set.