11-Letter Words Matching I_________M

There are 13 11-letter words that match I_________M. 3 are common words, such as IMPERIALISM and INCUNABULUM. A rarer one is INTERSYSTEM. 4 words contain a doubled letter.

Full list 13

imperialismincunabuluminterregnumillusionismimmanentisminfantilisminfusionisminsectariumintuitivismirredentismisochronismisomorphismintersystem

About this list

Words
13 (3 common words)
Common example
imperialism
Rare example
intersystem
Doubled letters
4
Ending in S
0

Questions

How many 11-letter words matching i_________m are there?

13. 3 of them are common words.

What is a common example?

IMPERIALISM is among the common words in this set.