15-Letter Words Matching ____O_____R____

There are 30 15-letter words that match ____O_____R____. 6 are common words, such as MICROELECTRONIC and MICROMETEORITES. A rarer one is VIDEOCONFERENCE. In this set, T is the most frequent open letter (27 words). 2 words contain a doubled letter.

Full list 30

Common words

microelectronicmicrometeoritesnitroglycerinesradiotelegraphsradiotelegraphytrigonometricalconnoisseurshipphotoelectricalphototelegraphyphototopographyphototypographypiezoelectrical
microelectronicmicrometeoritesnitroglycerinesradiotelegraphsradiotelegraphytrigonometricalconnoisseurshipphotoelectricalphototelegraphyphototopographyphototypographypiezoelectricalchemoautotrophyethnohistoriansethnohistoricalmethoxyfluranesmicrobarographsmicroelectrodesmicrometeoriticmicrometeoroidsnoncomputerizedphotoautotrophsphotoelectronicprotohistoriansradioautographsradioautographysocioculturallysociohistoricaluniformitariansvideoconference

About this list

Words
30 (6 common words)
Common example
microelectronic
Rare example
videoconference
Doubled letters
2
Ending in S
12
Most frequent letter
T (27)

Questions

How many 15-letter words matching ____o_____r____ are there?

30. 6 of them are common words.

What is a common example?

MICROELECTRONIC is among the common words in this set.