15-Letter Words Matching _A___C_________

There are 12 15-letter words that match _A___C_________. 4 are common words, such as BACKSCRATCHINGS and HALLUCINOGENICS. A rarer one is RADIOCHEMICALLY. In this set, I is the most frequent open letter (12 words). 6 words contain a doubled letter.

Full list 12

backscratchingshallucinogenicsparticularitiesparticularizinghallucinationalmacrocosmicallysarraceniaceousbackscatteringsparticipationalparticularisingparticularisticradiochemically

About this list

Words
12 (4 common words)
Common example
backscratchings
Rare example
radiochemically
Doubled letters
6
Ending in S
5
Most frequent letter
I (12)

Questions

How many 15-letter words matching _a___c_________ are there?

12. 4 of them are common words.

What is a common example?

BACKSCRATCHINGS is among the common words in this set.