10-Letter Words Matching S________M

There are 55 10-letter words that match S________M. 13 are common words, such as SANATORIUM and SANITARIUM. A rarer one is SUBOPTIMUM. In this set, I is the most frequent open letter (41 words). 11 words contain a doubled letter.

Full list 55

Common words

sanatoriumsanitariumscepticismschoolmarmschoolroomsecularismseparatismskepticismslipstreamspoonerismsubprogramsubstratum
sanatoriumsanitariumscepticismschoolmarmschoolroomsecularismseparatismskepticismslipstreamspoonerismsubprogramsubstratumsurrealismsalverformschematismseaborgiumseismogramsensualismsestertiumsimulacrumsinecurismspecialismspeciesismspermatiumsphenogramspongiformsporangiumstelliformstereogramstigmatismstilliformstramoniumstratiformstrongroomsubkingdomsubminimumsubproblemsubselliumsudatoriumsuffragismsybaritismsyncretismsanitoriumsarcoplasmsclerotiumsequestrumshadchanimshammashimsheriffdomsidestreamsolidarismstenothermstomodaeumstumblebumsuboptimum

About this list

Words
55 (13 common words)
Common example
sanatorium
Rare example
suboptimum
Doubled letters
11
Ending in S
0
Most frequent letter
I (41)

Questions

How many 10-letter words matching s________m are there?

55. 13 of them are common words.

What is a common example?

SANATORIUM is among the common words in this set.