12-Letter Words Matching ____TF______

There are 15 12-letter words that match ____TF______. 9 are common words, such as BOASTFULNESS and DOUBTFULLEST. A rarer one is TRISTFULNESS. 12 words contain a doubled letter.

Full list 15

boastfulnessdoubtfullestdoubtfulnesseventfulnessfaultfindersfaultfindingfruitfulnessrightfulnesstrustfulnesstightfittingfruitfullestreoutfittingsportfishingsportfulnesstristfulness

About this list

Words
15 (9 common words)
Common example
boastfulness
Rare example
tristfulness
Doubled letters
12
Ending in S
9

Questions

How many 12-letter words matching ____tf______ are there?

15. 9 of them are common words.

What is a common example?

BOASTFULNESS is among the common words in this set.