15-Letter Words Matching ______X________

There are 13 15-letter words that match ______X________. 2 are common words, such as AMBIDEXTERITIES and HOMOSEXUALITIES. A rarer one is PHOTOOXIDATIONS. In this set, I is the most frequent open letter (13 words). 2 words contain a doubled letter.

Full list 13

ambidexteritieshomosexualitieshyperextensionsambisexualitiesantisexualitieshyperexcitementhyperexcretionsmethylxanthinesparadoxicalnessparamyxovirusesparasexualitiesphotoexcitationphotooxidations

About this list

Words
13 (2 common words)
Common example
ambidexterities
Rare example
photooxidations
Doubled letters
2
Ending in S
11
Most frequent letter
I (13)

Questions

How many 15-letter words matching ______x________ are there?

13. 2 of them are common words.

What is a common example?

AMBIDEXTERITIES is among the common words in this set.