15-Letter Words Matching __E_O__________

There are 30 15-letter words that match __E_O__________. 2 are common words, such as PRECONDITIONING and PREPOSITIONALLY. A rarer one is STEROIDOGENESIS. In this set, I is the most frequent open letter (27 words). 2 words contain a doubled letter.

Full list 30

Common words

preconditioningprepositionallyacetophenetidinadenocarcinomasadenoidectomiesinexorabilitiesphenolphthaleinpiezoelectricalprenotificationadenohypophysesadenohypophysischemoautotrophy
preconditioningprepositionallyacetophenetidinadenocarcinomasadenoidectomiesinexorabilitiesphenolphthaleinpiezoelectricalprenotificationadenohypophysesadenohypophysischemoautotrophychemoreceptionschemotacticallychemotaxonomieschemotaxonomistchemotherapistsoveropinionatedoverorchestrateoverornamentingphenobarbitonesphenomenalisticphenomenologiesphenomenologistpreformationistpremodificationpreponderanciespreponderationssteroidogenesessteroidogenesis

About this list

Words
30 (2 common words)
Common example
preconditioning
Rare example
steroidogenesis
Doubled letters
2
Ending in S
14
Most frequent letter
I (27)

Questions

How many 15-letter words matching __e_o__________ are there?

30. 2 of them are common words.

What is a common example?

PRECONDITIONING is among the common words in this set.