Best English dictionary for Kindle?

I’m reading “Blood Meridian” on a Kindle and, beyond totally loving the book, am entertaining myself looking up words in the dictionary. Half of them are not found in the dictionary. Can anyone suggest a really comprehensive dictionary that I can install in place of the default? (It’s a Kindle Fire 2 if that makes a difference.)

I’m not attempting to look up the obviously Spanish words, these are English words.


(bump) Anyone??