15-Letter Words Matching I_____C________

There are 16 15-letter words that match I_____C________. 3 are common words, such as INEFFECTIVENESS and INJUDICIOUSNESS. A rarer one is INSTRUCTIVENESS. In this set, N is the most frequent open letter (15 words). 11 words contain a doubled letter.

Full list 16

ineffectivenessinjudiciousnessinterscholasticidenticalnessesimmunochemistryimperscriptibleineffectualnessinstructorshipsirrevocablenessillogicalnessesimmunocompetentincapacitationsindefectibilityineffaceabilityinefficaciouslyinstructiveness

About this list

Words
16 (3 common words)
Common example
ineffectiveness
Rare example
instructiveness
Doubled letters
11
Ending in S
9
Most frequent letter
N (15)

Questions

How many 15-letter words matching i_____c________ are there?

16. 3 of them are common words.

What is a common example?

INEFFECTIVENESS is among the common words in this set.