11-Letter Words Matching _____E_F___

There are 18 11-letter words that match _____E_F___. 5 are common words, such as AFTEREFFECT and CHICKENFEED. A rarer one is TUMBLERFULS. In this set, R is the most frequent open letter (12 words). 5 words contain a doubled letter.

Full list 18

aftereffectchickenfeedcounterfeitcounterfoilhundredfoldpitcherfulstriggerfishantiwelfarecockneyfiedcockneyfiescounterfirecounterflowdropperfulsplatterfulssatchelfulssemideifiedsemideifiestumblerfuls

About this list

Words
18 (5 common words)
Common example
aftereffect
Rare example
tumblerfuls
Doubled letters
5
Ending in S
7
Most frequent letter
R (12)

Questions

How many 11-letter words matching _____e_f___ are there?

18. 5 of them are common words.

What is a common example?

AFTEREFFECT is among the common words in this set.