15-Letter Words Matching _____D________Y

There are 12 15-letter words that match _____D________Y. 3 are common words, such as CONFIDENTIALITY and LACKADAISICALLY. A rarer one is UNTRADITIONALLY. In this set, I is the most frequent open letter (12 words). 5 words contain a doubled letter.

Full list 12

confidentialitylackadaisicallyunconditionallyimponderabilityinterdependencyorthodonticallyreproducibilityserendipitouslysynecdochicallyineradicabilitysplendiferouslyuntraditionally

About this list

Words
12 (3 common words)
Common example
confidentiality
Rare example
untraditionally
Doubled letters
5
Ending in S
0
Most frequent letter
I (12)

Questions

How many 15-letter words matching _____d________y are there?

12. 3 of them are common words.

What is a common example?

CONFIDENTIALITY is among the common words in this set.