What Does 'Straight' whiskey mean?

During our last bourbon tasting at Vino Etc., I was a number of really good questions.  One attendee queried, "What does straight whiskey/bourbon mean?  What is a straight whiskey?"

My initial response was, "Well, like many aspects of whiskey and bourbon, the answer is a bit vague...in reality, it doesn't mean anything more than what we today call bourbon."

Well, I was wrong.  

Unlike what defines bourbon as a bourbon, an act of congress, in 2016 the United States Government passed a law defining all sorts of specifications around whiskey. 

The Electronic Code of Federal Regulations’ Title 27.1(A)(5)(c), current as of April 19th, 2016, governs the “Standards of Identity for Distilled Spirits.”

"To be designated as “straight,” whiskies must conform to the aforementioned standards (distilled at less than 160 proof, stored at less than 125 proof, made from grain) and then they must be stored in the appropriate type of oak containers for a period of two or more years. No other whiskies may be designated “straight.” “Straight whisky” also includes mixtures of straight whiskies of the same type, but they must be produced in the same state."

When looking at the entire legal description, it appears that 99% of all whiskey is "straight".  

Cheers!

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