Words that contain 'n' and end in 'mas'

What's the largest word you can make with this list?
The longest word is 17 letters, which is 'sarcoenchondromas'.

What's the highest number of points you can get in Scrabble from this list of words that contain 'n' and end in 'mas'?
Using this combination of letters, the best word to play is 'johnsmas' which scores 20 in Scrabble.

What is an example of a unusual word from this list?
Our favorite peculiar word from this list is 'martinmas'. 'Martinmas' is defined as "The feast of St. Martin, the eleventh of November; -- often called martlemans. Martinmas summer, a period of calm, warm weather often experienced about the time of Martinmas; Indian summer. Percy Smith.", according to the English dictionary.

Which word that has 'n' in and ends with 'mas' is the most common word in the dictionary?
We've identified that 'anathemas' is the 67014^th most common word.

How many viable words are possible to make using the combination specified?
From this page of words that have 'n' in and end with 'mas', Dictionarypedia has found 60 effective entries that are available overall.