12-Letter Words Matching ________I_I_

There are 40 12-letter words that match ________I_I_. 5 are common words, such as APPENDICITIS and ENCEPHALITIC. A rarer one is SPAGHETTINIS. In this set, T is the most frequent open letter (32 words). 3 words contain a doubled letter.

Full list 40

Common words

appendicitisencephaliticencephalitistranspacificunscientificantirachiticbibliophilicdiphtheriticendocarditiseosinophilicheterocliticlymphangitis
appendicitisencephaliticencephalitistranspacificunscientificantirachiticbibliophilicdiphtheriticendocarditiseosinophilicheterocliticlymphangitisnonparasiticoneirocriticophthalmitisoverexplicitoverspecificpancreatitispericarditisperineuritisphospholipidphotoactinicpolyneuritispyonephritisthermophilicanorthositicantipruriticdaunorubicinendometritiseosinophiliaepididymitisfolliculitismonospecificnepheliniticneutrophilicnucleophilicphosphatidicphosphoriticpolypeptidicspaghettinis

About this list

Words
40 (5 common words)
Common example
appendicitis
Rare example
spaghettinis
Doubled letters
3
Ending in S
14
Most frequent letter
T (32)

Questions

How many 12-letter words matching ________i_i_ are there?

40. 5 of them are common words.

What is a common example?

APPENDICITIS is among the common words in this set.