15-Letter Words Matching ____________O_Y

There are 19 15-letter words that match ____________O_Y. 2 are common words, such as NONCONTRIBUTORY and NONINFLAMMATORY. A rarer one is POSTSTIMULATORY. In this set, O is the most frequent open letter (18 words). 4 words contain a doubled letter.

Full list 19

noncontributorynoninflammatorycholecystectomydissatisfactoryethnomusicologyexcommunicatorylepidopterologyneurophysiologypaleopsychologyprocrastinatoryprognosticatorypsychopathologyhistophysiologyimmunopathologymicromorphologyneuropsychologypathophysiologyphysiopathologypoststimulatory

About this list

Words
19 (2 common words)
Common example
noncontributory
Rare example
poststimulatory
Doubled letters
4
Ending in S
0
Most frequent letter
O (18)

Questions

How many 15-letter words matching ____________o_y are there?

19. 2 of them are common words.

What is a common example?

NONCONTRIBUTORY is among the common words in this set.