13-Letter Words Matching __I_________L

There are 12 13-letter words that match __I_________L. 4 are common words, such as PHILOSOPHICAL and SEISMOLOGICAL. A rarer one is UNIDEOLOGICAL. In this set, A is the most frequent open letter (12 words). 2 words contain a doubled letter.

Full list 12

philosophicalseismologicaltricentennialunintentionalorientationalquindecennialuninfluentialepiphenomenalorismologicalovipositionaltritheisticalunideological

About this list

Words
12 (4 common words)
Common example
philosophical
Rare example
unideological
Doubled letters
2
Ending in S
0
Most frequent letter
A (12)

Questions

How many 13-letter words matching __i_________l are there?

12. 4 of them are common words.

What is a common example?

PHILOSOPHICAL is among the common words in this set.