This document lists and defines 40 common American slang words and phrases. It explains that some American idioms like "bought the farm", "spill the beans", and "shoot the breeze" derive from specific historical contexts that may not be obvious to British English speakers. The document also notes several phrases like "Monday morning quarterback" and "ride shotgun" use metaphors from American football or the American Old West that would be unfamiliar to many non-Americans. Overall, the document highlights how some ubiquitous American slang terms can have obscure origins or subtle meanings that may confuse English speakers from other countries.