12-Letter Words Matching __I_____O___

There are 21 12-letter words that match __I_____O___. 7 are common words, such as AVITAMINOSES and AVITAMINOSIS. A rarer one is ZWITTERIONIC. 7 words contain a doubled letter.

Full list 21

avitaminosesavitaminosischickenpoxeschildproofedphilharmonicrhinocerosesthistledownsclimatologiccrinklerootsepidiascopesepimorphosisepitheliomasflittermouseslipperwortswhitethroatsavitaminoticshittimwoodssniperscopestribespeopleunillusionedzwitterionic

About this list

Words
21 (7 common words)
Common example
avitaminoses
Rare example
zwitterionic
Doubled letters
7
Ending in S
13

Questions

How many 12-letter words matching __i_____o___ are there?

21. 7 of them are common words.

What is a common example?

AVITAMINOSES is among the common words in this set.