The biggest word from this list is how many characters? There are 11 characters in the word pseudotsuga, that makes it the largest word we have.
What's the max number of words one can create from this combination of letters? There are 2 words overall.
What's the highest scoring Scrabble word you can make? As there is only 2 combinations to pick from, the only word you can play for is eurypyga scoring 17 points.