13-Letter Words Matching ________O_O__

There are 33 13-letter words that match ________O_O__. 4 are common words, such as BIOTECHNOLOGY and ENDOCRINOLOGY. A rarer one is TRIAMCINOLONE. In this set, L is the most frequent open letter (25 words). 5 words contain a doubled letter.

Full list 33

Common words

biotechnologyendocrinologyinsectivorousophthalmologyallochthonousautochthonousgeochronologygeomorphologygraminivoroushelminthologyheterosporousnonhomologous
biotechnologyendocrinologyinsectivorousophthalmologyallochthonousautochthonousgeochronologygeomorphologygraminivoroushelminthologyheterosporousnonhomologousnumismatologypaleethnologypancreatotomyphenomenologypsychobiologyroentgenologysedimentologysplanchnologysystematologythremmatologytubuliflorouscavernicolouschemotaxonomychronobiologycryptozoologyecophysiologyepizootiologyisochromosomenonautonomouspolychotomoustriamcinolone

About this list

Words
33 (4 common words)
Common example
biotechnology
Rare example
triamcinolone
Doubled letters
5
Ending in S
10
Most frequent letter
L (25)

Questions

How many 13-letter words matching ________o_o__ are there?

33. 4 of them are common words.

What is a common example?

BIOTECHNOLOGY is among the common words in this set.