13-Letter Words Matching _____D____S__

There are 12 13-letter words that match _____D____S__. 5 are common words, such as ACCORDIONISTS and AVOIRDUPOISES. A rarer one is UNREADINESSES. In this set, I is the most frequent open letter (12 words). 6 words contain a doubled letter.

Full list 12

accordionistsavoirdupoisesincredulouslyorthodontistsperiodontistsincendiarismsinterdiffusedinterdiffusespalindromiststhreadinessesunhandinessesunreadinesses

About this list

Words
12 (5 common words)
Common example
accordionists
Rare example
unreadinesses
Doubled letters
6
Ending in S
10
Most frequent letter
I (12)

Questions

How many 13-letter words matching _____d____s__ are there?

12. 5 of them are common words.

What is a common example?

ACCORDIONISTS is among the common words in this set.