15-Letter Words Matching ____O____O_____

There are 58 15-letter words that match ____O____O_____. 5 are common words, such as MICROBIOLOGICAL and MICROBIOLOGISTS. A rarer one is SOCIOHISTORICAL. In this set, I is the most frequent open letter (55 words). 7 words contain a doubled letter.

Full list 58

Common words

microbiologicalmicrobiologistsmicrometeoritespaleontologistsprepositionallymicrophotographmicrosporophyllpaleontologicalphotomicrographphotomicroscoperadiomicrometerradiophotograph
microbiologicalmicrobiologistsmicrometeoritespaleontologistsprepositionallymicrophotographmicrosporophyllpaleontologicalphotomicrographphotomicroscoperadiomicrometerradiophotographsociobiologicalsociobiologistssubcontraoctaveastrobiologistsastrophotographcompositionallyethnohistoriansethnohistoricalhistopathologichydrobiologicalhydrobiologistshydroxyprolineslignosulfonatesmacrophotographmicroanatomicalmicrometeoriticmicrometeoroidsmicrophotometermicrophotometrymicroradiographmicrosporocytesneuroanatomicalneuroanatomistsneurobiologicalneurobiologistsneuropathologicoveropinionatedpaleobiologicalpaleobiologistspaleoecologicalpaleoecologistspaleozoologicalpaleozoologistsphotobiologicalphotobiologistsphotodissociatephotogeologicalphotogeologistsphotolithographphotoperiodismsphytopathogenicprotohistoriansprotozoologistsradiobiologicalradiobiologistssociohistorical

About this list

Words
58 (5 common words)
Common example
microbiological
Rare example
sociohistorical
Doubled letters
7
Ending in S
22
Most frequent letter
I (55)

Questions

How many 15-letter words matching ____o____o_____ are there?

58. 5 of them are common words.

What is a common example?

MICROBIOLOGICAL is among the common words in this set.