15-Letter Words Matching ___T__R________

There are 21 15-letter words that match ___T__R________. 8 are common words, such as BROTHERLINESSES and FEATHERBEDDINGS. A rarer one is SUBTERRANEOUSLY. In this set, I is the most frequent open letter (20 words). 12 words contain a doubled letter.

Full list 21

brotherlinessesfeatherbeddingsmultiprocessingmultiprocessorspasteurizationsweatherizationsweatherproofingweatherstrippedoxytetracyclinephototransistorweatherboardingexothermicitiesfeatherstitchedfeatherstitchesmontmorillonitephotogrammetricphotoproductionphototropicallyplutocraticallypostirradiationsubterraneously

About this list

Words
21 (8 common words)
Common example
brotherlinesses
Rare example
subterraneously
Doubled letters
12
Ending in S
7
Most frequent letter
I (20)

Questions

How many 15-letter words matching ___t__r________ are there?

21. 8 of them are common words.

What is a common example?

BROTHERLINESSES is among the common words in this set.