15-Letter Words Matching ____O_I________

There are 53 15-letter words that match ____O_I________. 9 are common words, such as AUTHORITATIVELY and EXPLOSIVENESSES. A rarer one is TOMBOYISHNESSES. In this set, I is the most frequent open letter (45 words). 16 words contain a doubled letter.

Full list 53

Common words

authoritativelyexplosivenesseshistoriographerimprovisationalmicrobiologicalmicrobiologistspersonificationphotofinishingsprepositionallycommodificationhistoriographicimprovisatorial
authoritativelyexplosivenesseshistoriographerimprovisationalmicrobiologicalmicrobiologistspersonificationphotofinishingsprepositionallycommodificationhistoriographicimprovisatorialmicromillimeterphotomicrographphotomicroscopeprenotificationradiomicrometersociobiologicalsociobiologistssociolinguisticsyllogisticallyunprofitabilityastrobiologistsbenzodiazepinescompositionallycorrosivenessesdyslogisticallyethnohistoriansethnohistoricalgnotobioticallyhydrobiologicalhydrobiologistshypnotizabilitymicrodissectionneurobiologicalneurobiologistsneurofibrillaryoveropinionatedpaleobiologicalpaleobiologistsphotobiologicalphotobiologistsphotodissociatephotolithographpictorialnessespremodificationpromotivenessesprotohistorianspurposivenessesradiobiologicalradiobiologistssociohistoricaltomboyishnesses

About this list

Words
53 (9 common words)
Common example
authoritatively
Rare example
tomboyishnesses
Doubled letters
16
Ending in S
18
Most frequent letter
I (45)

Questions

How many 15-letter words matching ____o_i________ are there?

53. 9 of them are common words.

What is a common example?

AUTHORITATIVELY is among the common words in this set.