12-Letter Words Matching A_________A_

There are 55 12-letter words that match A_________A_. 21 are common words, such as ABERRATIONAL and ABRACADABRAS. A rarer one is AZOOSPERMIAS. In this set, I is the most frequent open letter (50 words). 12 words contain a doubled letter.

Full list 55

Common words

aberrationalabracadabrasaeronauticalagoraphobiasagriculturalalphabeticalanaesthesiasantediluviananticlericalantimacassarantimalarialantithetical
aberrationalabracadabrasaeronauticalagoraphobiasagriculturalalphabeticalanaesthesiasantediluviananticlericalantimacassarantimalarialantitheticalarchdiocesanarchetypicalarithmeticalarrhythmicalartillerymanastrologicalastronomicalasymmetricalaudiologicalaccusatorialadaptationalagrochemicalalbuminuriasallotropicalambulancemanamphisbaenasanacoluthiasaniseikoniasantemeridiananticolonialantirationalapologeticalapparitionalappendicularappositionalaspirationalasymptoticalautocraticaladjustmentalaestheticianagrichemicalamygdaloidalannexationalanthologicalanticulturalantinationalantonomasiasaquaculturalarchesporialarchosaurianastrocytomasatheoreticalazoospermias

About this list

Words
55 (21 common words)
Common example
aberrational
Rare example
azoospermias
Doubled letters
12
Ending in S
10
Most frequent letter
I (50)

Questions

How many 12-letter words matching a_________a_ are there?

55. 21 of them are common words.

What is a common example?

ABERRATIONAL is among the common words in this set.