15-Letter Words Matching _AT____________

There are 20 15-letter words that match _AT____________. 8 are common words, such as CATEGORIZATIONS and LATITUDINARIANS. A rarer one is WATERLESSNESSES. In this set, I is the most frequent open letter (18 words). 5 words contain a doubled letter.

Full list 20

categorizationslatitudinariansmaterializationnationalizationnaturalizationspaterfamiliasesrationalizationtatterdemalionscataclysmicallybathymetricallycatheterizationfatheadednesseslatensificationlateralizationsmaterfamiliasesmathematizationpatentabilitiespathogenicitiespathophysiologywaterlessnesses

About this list

Words
20 (8 common words)
Common example
categorizations
Rare example
waterlessnesses
Doubled letters
5
Ending in S
11
Most frequent letter
I (18)

Questions

How many 15-letter words matching _at____________ are there?

20. 8 of them are common words.

What is a common example?

CATEGORIZATIONS is among the common words in this set.