13-Letter Words Matching ____A__O_____

There are 51 13-letter words that match ____A__O_____. 12 are common words, such as COMPANIONABLE and COMPANIONABLY. A rarer one is WOLLASTONITES. In this set, I is the most frequent open letter (44 words). 16 words contain a doubled letter.

Full list 51

Common words

companionablecompanionablycompanionshipcompanionwaysdisharmoniouseducationallyisolationismsisolationistsoperationallysemiautomaticsensationallyvibraphonists
companionablecompanionablycompanionshipcompanionwaysdisharmoniouseducationallyisolationismsisolationistsoperationallysemiautomaticsensationallyvibraphonistsdeviationismsdeviationistseducationistsgradationallynoncarbonatednonpathogenicradiationallyrefractometerundiagnosableavocationallydisharmonizeddisharmonizeseducationesesinflationismsinflationistsintrathoracicisocarboxazidnonlandownersnonrandomnessoperationismsoperationistspentaploidiesprivatdocentsprivatdozentsprobationallyradiationlessrefractometrysalvationismssituationallysympatholytictetraploidiesthalassocracythalassocratstricarboxylicultraviolencevaluationallyvariationallyvibrationlesswollastonites

About this list

Words
51 (12 common words)
Common example
companionable
Rare example
wollastonites
Doubled letters
16
Ending in S
25
Most frequent letter
I (44)

Questions

How many 13-letter words matching ____a__o_____ are there?

51. 12 of them are common words.

What is a common example?

COMPANIONABLE is among the common words in this set.