15-Letter Words Matching ____R______O___

There are 21 15-letter words that match ____R______O___. 6 are common words, such as ATHEROSCLEROSES and ATHEROSCLEROSIS. A rarer one is INTERELECTRONIC. In this set, L is the most frequent open letter (19 words). 6 words contain a doubled letter.

Full list 21

atherosclerosesatherosclerosisconfrontationaldisproportionalnonprofessionalsubprofessionalatheroscleroticinterrogationallabyrinthodontsmalpractitionerpleuropneumoniapreprofessionalupperclasswomanupperclasswomendisproportionedenterogastroneshyperfunctionalinterbehavioralinterdivisionalinterelectrodesinterelectronic

About this list

Words
21 (6 common words)
Common example
atheroscleroses
Rare example
interelectronic
Doubled letters
6
Ending in S
5
Most frequent letter
L (19)

Questions

How many 15-letter words matching ____r______o___ are there?

21. 6 of them are common words.

What is a common example?

ATHEROSCLEROSES is among the common words in this set.