9-Letter Words Matching ___A____O

There are 12 9-letter words that match ___A____O. 3 are common words, such as ARMADILLO and CABALLERO. A rarer one is TOMATILLO. In this set, A is the most frequent open letter (9 words). 9 words contain a doubled letter.

Full list 12

armadillocaballerocigarilloandantinocalamancolazarettopaparazzosgraffitozapateadotamarillotomatillostrappado

About this list

Words
12 (3 common words)
Common example
armadillo
Rare example
tomatillo
Doubled letters
9
Ending in S
0
Most frequent letter
A (9)

Questions

How many 9-letter words matching ___a____o are there?

12. 3 of them are common words.

What is a common example?

ARMADILLO is among the common words in this set.