10-Letter Words Matching ___S_____M

There are 22 10-letter words that match ___S_____M. 4 are common words, such as CLASSICISM and CONSORTIUM. A rarer one is PROSTATISM. In this set, I is the most frequent open letter (18 words). 6 words contain a doubled letter.

Full list 22

classicismconsortiumprosceniumsubstratumblastodermbolshevismboosterismepisternumgnosticismhaustellumhaustoriumplasmodiumprostomiumseismogramsensualismsubselliumwhiskbroomhipsterismmessianismplasmodesmpresentismprostatism

About this list

Words
22 (4 common words)
Common example
classicism
Rare example
prostatism
Doubled letters
6
Ending in S
0
Most frequent letter
I (18)

Questions

How many 10-letter words matching ___s_____m are there?

22. 4 of them are common words.

What is a common example?

CLASSICISM is among the common words in this set.