15-Letter Words Matching _____TR________

There are 25 15-letter words that match _____TR________. 9 are common words, such as CLAUSTROPHOBIAS and ILLUSTRIOUSNESS. A rarer one is SYMMETRIZATIONS. In this set, I is the most frequent open letter (25 words). 8 words contain a doubled letter.

Full list 25

Common words

claustrophobiasillustriousnessindoctrinationsindustrializingindustriousnesspedestrianizingredistributionstrinitrotolueneuncontroversialbioastronauticsoxytetracyclinephototransistor
claustrophobiasillustriousnessindoctrinationsindustrializingindustriousnesspedestrianizingredistributionstrinitrotolueneuncontroversialbioastronauticsoxytetracyclinephototransistorsinistrodextraltrinitrobenzeneanisotropicallygeometrizationsindustrialisingmagistraticallymisattributionsnonastronomicalnonmatriculatednonmetropolitanphototropicallysymmetricalnesssymmetrizations

About this list

Words
25 (9 common words)
Common example
claustrophobias
Rare example
symmetrizations
Doubled letters
8
Ending in S
10
Most frequent letter
I (25)

Questions

How many 15-letter words matching _____tr________ are there?

25. 9 of them are common words.

What is a common example?

CLAUSTROPHOBIAS is among the common words in this set.