15-Letter Words Matching __OS___________

There are 17 15-letter words that match __OS___________. 1 are common words, such as PHOSPHORESCENCE and CROSSOPTERYGIAN. A rarer one is PROSTHODONTISTS. In this set, I is the most frequent open letter (16 words). 3 words contain a doubled letter.

Full list 17

phosphorescencecrossopterygianphosphocreatinephosphoproteinsphosphorylationproselytizationprostatectomiesbiostatisticianbiostratigraphybiosystematistscrosslinguisticgeostrophicallyphosphatizationphosphorylatingphosphorylativeprosopographiesprosthodontists

About this list

Words
17 (1 common words)
Common example
phosphorescence
Rare example
prosthodontists
Doubled letters
3
Ending in S
5
Most frequent letter
I (16)

Questions

How many 15-letter words matching __os___________ are there?

17. 1 of them are common words.

What is a common example?

PHOSPHORESCENCE is among the common words in this set.