12-Letter Words Matching A_____B_____

There are 19 12-letter words that match A_____B_____. 4 are common words, such as ADAPTABILITY and ADVISABILITY. A rarer one is AUTOMOBILITY. In this set, I is the most frequent open letter (19 words). 2 words contain a doubled letter.

Full list 19

adaptabilityadvisabilityautomobilingavailabilityadmirabilityaeroembolismalienabilityamphisbaenasadoptabilityagreeabilityalterabilityamobarbitalsamphisbaenicanaerobiosesanaerobiosisantiliberalsassumabilityautomobilistautomobility

About this list

Words
19 (4 common words)
Common example
adaptability
Rare example
automobility
Doubled letters
2
Ending in S
5
Most frequent letter
I (19)

Questions

How many 12-letter words matching a_____b_____ are there?

19. 4 of them are common words.

What is a common example?

ADAPTABILITY is among the common words in this set.