15-Letter Words Matching __D___________Y

There are 19 15-letter words that match __D___________Y. 4 are common words, such as BIDIRECTIONALLY and INDETERMINATELY. A rarer one is SIDESPLITTINGLY. In this set, I is the most frequent open letter (18 words). 9 words contain a doubled letter.

Full list 19

bidirectionallyindeterminatelyradiotelegraphyunderstandinglyfideicommissaryhydrometallurgyhydrostaticallyindefensibilityindigestibilityindissolubilityradiometricallyundependabilityeudiometricallyindefeasibilityindefectibilityradioautographyradiochemicallyreduplicativelysidesplittingly

About this list

Words
19 (4 common words)
Common example
bidirectionally
Rare example
sidesplittingly
Doubled letters
9
Ending in S
0
Most frequent letter
I (18)

Questions

How many 15-letter words matching __d___________y are there?

19. 4 of them are common words.

What is a common example?

BIDIRECTIONALLY is among the common words in this set.