13-Letter Words Matching _____R__R____

There are 20 13-letter words that match _____R__R____. 8 are common words, such as ANCHORPERSONS and INAPPROPRIATE. A rarer one is WINTERBERRIES. In this set, E is the most frequent open letter (16 words). 4 words contain a doubled letter.

Full list 20

anchorpersonsinappropriatekindergartenskindergartnermasterstrokesnonperformingoutperformingrutherfordiumelectrographsspectrographsspectrographyantiarthriticantiarthritischondrocranianonperformersoverprogramedreappropriatesilverberriessubparagraphswinterberries

About this list

Words
20 (8 common words)
Common example
anchorpersons
Rare example
winterberries
Doubled letters
4
Ending in S
10
Most frequent letter
E (16)

Questions

How many 13-letter words matching _____r__r____ are there?

20. 8 of them are common words.

What is a common example?

ANCHORPERSONS is among the common words in this set.