A fascinating dictionary of terms from the Wild West of 1850 to 1900 lists the origins and meanings of many currently used expressions and phrases, noting their frequent adaptations from original Mexican words.
This dictionary lists the dialects of English in use in the West of the United States of America in the latter part of the 19th Century. The hybrid language of the frontier is revealed in this compilation of terms used by the cattlemen, frontiersmen, scouts, cowboys, and gamblers.
Nice reference books for anyone reading or writing books set in the 'Old West' - from a writers point of view it is just a pity it doesn't allow for looking up what the 'Westernism' for a modern word or phrase would be, just the other way around.