14-Letter Words Matching A_______T_____

There are 21 14-letter words that match A_______T_____. 8 are common words, such as AFOREMENTIONED and ALLITERATIVELY. A rarer one is AXISYMMETRICAL. In this set, I is the most frequent open letter (21 words). 8 words contain a doubled letter.

Full list 21

aforementionedalliterativelyanaesthetizinganathematizingappendectomiesappreciativelyarchitectonicsarticulatenessacrylonitrilesanticapitalistantimilitarismacceleratinglyaccumulativelyaeroelasticityaminopeptidaseantiapartheidsanticapitalismantimilitaristapocalypticismassistantshipsaxisymmetrical

About this list

Words
21 (8 common words)
Common example
aforementioned
Rare example
axisymmetrical
Doubled letters
8
Ending in S
6
Most frequent letter
I (21)

Questions

How many 14-letter words matching a_______t_____ are there?

21. 8 of them are common words.

What is a common example?

AFOREMENTIONED is among the common words in this set.