13-Letter Words Matching _R____G______

There are 18 13-letter words that match _R____G______. 3 are common words, such as CRYPTOGRAPHER and PROLONGATIONS. A rarer one is PROTEOGLYCANS. In this set, O is the most frequent open letter (18 words). 3 words contain a doubled letter.

Full list 18

cryptographerprolongationspromulgationscryptographicfrontogenesisirreligiouslyorganogenesisprediagnosticfrontogenesesirreligionistorganogenesesorganogeneticpreganglionicpreprogramingpreprogrammedprestigiouslyprostaglandinproteoglycans

About this list

Words
18 (3 common words)
Common example
cryptographer
Rare example
proteoglycans
Doubled letters
3
Ending in S
7
Most frequent letter
O (18)

Questions

How many 13-letter words matching _r____g______ are there?

18. 3 of them are common words.

What is a common example?

CRYPTOGRAPHER is among the common words in this set.