13-Letter Words Matching _T________O__

There are 15 13-letter words that match _T________O__. 2 are common words, such as STEPPINGSTONE and STUPEFACTIONS. A rarer one is STROBILATIONS. In this set, S is the most frequent open letter (15 words). 2 words contain a doubled letter.

Full list 15

steppingstonestupefactionsstenopetalousstenophyllousstercoraceoussternforemoststernutationsstridulationsstrobilaceouseternizationsetherizationsstereopticonsstigmasterolsstoloniferousstrobilations

About this list

Words
15 (2 common words)
Common example
steppingstone
Rare example
strobilations
Doubled letters
2
Ending in S
13
Most frequent letter
S (15)

Questions

How many 13-letter words matching _t________o__ are there?

15. 2 of them are common words.

What is a common example?

STEPPINGSTONE is among the common words in this set.