15-Letter Words Matching ________S_____Y

There are 15 15-letter words that match ________S_____Y. 2 are common words, such as INFINITESIMALLY and LACKADAISICALLY. A rarer one is VISCOELASTICITY. In this set, I is the most frequent open letter (15 words). 7 words contain a doubled letter.

Full list 15

infinitesimallylackadaisicallyarchiepiscopacyinterpersonallyneurophysiologyphotoelasticityretrogressivelyastrophysicallyhistophysiologyincommensurablymicrophysicallymicroseismicitypathophysiologysuperplasticityviscoelasticity

About this list

Words
15 (2 common words)
Common example
infinitesimally
Rare example
viscoelasticity
Doubled letters
7
Ending in S
0
Most frequent letter
I (15)

Questions

How many 15-letter words matching ________s_____y are there?

15. 2 of them are common words.

What is a common example?

INFINITESIMALLY is among the common words in this set.