12-Letter Words Matching ____RF______

There are 21 12-letter words that match ____RF______. 7 are common words, such as CHEERFULLEST and CHEERFULNESS. A rarer one is WATERFOWLING. In this set, E is the most frequent open letter (20 words). 6 words contain a doubled letter.

Full list 21

cheerfullestcheerfulnesscolorfulnessimperfectioninterferencespearfishingunderfeedingimperfectiveinterfertilepowerfulnessunderfundingunperforatedcosurfactantinterfacingsinterfacultyinterfluvialinterfoldinginterfusionswaterfloodedwaterfowlerswaterfowling

About this list

Words
21 (7 common words)
Common example
cheerfullest
Rare example
waterfowling
Doubled letters
6
Ending in S
6
Most frequent letter
E (20)

Questions

How many 12-letter words matching ____rf______ are there?

21. 7 of them are common words.

What is a common example?

CHEERFULLEST is among the common words in this set.