15-Letter Words Matching ____I____U_____

There are 18 15-letter words that match ____I____U_____. 5 are common words, such as ARCHITECTURALLY and CARNIVOROUSNESS. A rarer one is SILVICULTURISTS. In this set, S is the most frequent open letter (16 words). 12 words contain a doubled letter.

Full list 18

architecturallycarnivorousnesshorticulturistsmellifluousnessmultilingualismduplicitousnesshorticulturallyodoriferousnesspestiferousnessprecipitousnesspromiscuousnesscitriculturistsfissiparousnessfloriculturistsfloriferousnessoveringenuitiessilviculturallysilviculturists

About this list

Words
18 (5 common words)
Common example
architecturally
Rare example
silviculturists
Doubled letters
12
Ending in S
14
Most frequent letter
S (16)

Questions

How many 15-letter words matching ____i____u_____ are there?

18. 5 of them are common words.

What is a common example?

ARCHITECTURALLY is among the common words in this set.