13-Letter Words Matching O____I_______

There are 21 13-letter words that match O____I_______. 7 are common words, such as OBLIVIOUSNESS and OBNOXIOUSNESS. A rarer one is OVERWITHHOLDS. 9 words contain a doubled letter.

Full list 21

obliviousnessobnoxiousnessofficiousnessoptimizationsorganizationsossificationsoverwinteringoccasionalismoverdiversifyoverrighteousovertightenedobnubilationsoppositionistoptimisationsorganisationsoutglitteringovercivilizedoverdirectingoverdiscountsoverdiversityoverwithholds

About this list

Words
21 (7 common words)
Common example
obliviousness
Rare example
overwithholds
Doubled letters
9
Ending in S
12

Questions

How many 13-letter words matching o____i_______ are there?

21. 7 of them are common words.

What is a common example?

OBLIVIOUSNESS is among the common words in this set.