You'll have to take our word for it when we say there a few plausible explanations for the term. One theory backed by the American Heritage Dictionary proposes the original phrase was actually "butt naked." The phrase was then cleaned up to "buck naked" so it could be used in polite company. A post on a message board forwards the idea that "buck" in this sense is an adverb meaning "stark" or "completely."
Brit wordsmith Michael Quinon has another theory. He's of the notion that "buck" and "buff," another term to describe nudity, are both derived from buckskin and buffalo hides. He argues that buff leather is tan in color, much like the color of the Europeans' skin after being in the sun. This led to the expression "to be in the buff," or naked. Thomas Dekker was the first to go on record with the term when he said in 1602, "I go in stag, in buff." The assumption is that "buck naked" has a similar derivation from buckskin.
Who's right? We don't know. But the Atlantic Monthly offers a humorous look at the way we describe degrees of nudity.
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