13-Letter Words Matching ____RF_______

There are 21 13-letter words that match ____RF_______. 8 are common words, such as COLORFASTNESS and IMPERFECTIONS. A rarer one is WATERFOWLINGS. In this set, E is the most frequent open letter (20 words). 4 words contain a doubled letter.

Full list 21

colorfastnessimperfectionsimperfectnessinterferencespaterfamiliassuperficiallysuperfluitiessuperfluouslyimperfectivesmaterfamiliassuperfamiliessuperfetationcosurfactantshyperfunctioninterfamilialinterferogramsuperfluidityunderfinancedunperformablewaterfloodingwaterfowlings

About this list

Words
21 (8 common words)
Common example
colorfastness
Rare example
waterfowlings
Doubled letters
4
Ending in S
11
Most frequent letter
E (20)

Questions

How many 13-letter words matching ____rf_______ are there?

21. 8 of them are common words.

What is a common example?

COLORFASTNESS is among the common words in this set.