Words that contain 'x' and end in 'ix'

Which word that has 'x' in and ends with 'ix' is the most popular word in the dictionary?
We've discovered that 'xix' is the 23239^th most common word.

What's the max number of words you could assemble using this list?
You could create 7 words with the specified combination.

Which word that has 'x' in and ends with 'ix' is the most unique?
One example of an uncommon word from this page goes to 'rixatrix'. The definition of 'rixatrix' is as follows: "A scolding or quarrelsome woman; a scold. Burrill.".

In Scrabble, what's the highest possible score possible from words that have 'x' in and end with 'ix'?
From this combination, the best word to play is 'coxendix' which scores 25 in Scrabble.

What is the largest word you can make using this list?
'exterminatrix', and consists of 13 characters.