13-Letter Words Matching ____OI_______

There are 18 13-letter words that match ____OI_______. 3 are common words, such as EXPLOITATIONS and RADIOISOTOPES. A rarer one is THYROIDITISES. 1 words contain a doubled letter.

Full list 18

exploitationsradioisotopestortoiseshelladenoidectomyaneroidographmastoidectomymastoiditidesamyloidosisesmastoiditisesmicroinjectedphotoionizingpremoisteningradioisotopicsigmoidoscopysteroidogenicthyroidectomythyroiditidesthyroiditises

About this list

Words
18 (3 common words)
Common example
exploitations
Rare example
thyroiditises
Doubled letters
1
Ending in S
7

Questions

How many 13-letter words matching ____oi_______ are there?

18. 3 of them are common words.

What is a common example?

EXPLOITATIONS is among the common words in this set.