14-Letter Words Matching I_______R_____

There are 12 14-letter words that match I_______R_____. 4 are common words, such as IDIOSYNCRASIES and INTERMARRIAGES. A rarer one is ISOPROTERENOLS. In this set, E is the most frequent open letter (12 words). 5 words contain a doubled letter.

Full list 12

idiosyncrasiesintermarriagesinterspersionsirregularitiesintermigrationimmunosorbentsinspectorshipsinstructressesintercorrelateinteroperativeintersterilityisoproterenols

About this list

Words
12 (4 common words)
Common example
idiosyncrasies
Rare example
isoproterenols
Doubled letters
5
Ending in S
8
Most frequent letter
E (12)

Questions

How many 14-letter words matching i_______r_____ are there?

12. 4 of them are common words.

What is a common example?

IDIOSYNCRASIES is among the common words in this set.