Sawbuck is a US term that may refer to a device and is a slang term for a U.S. currency bill.
A sawbuck is a device for holding wood so that it may be cut into pieces. Easily made in the field from rough material, it consists of an "X" form at each end which are joined by cross bars below the intersections of the X's. The stock to be cut is placed in the V's formed above the intersections of the X's.
A sawbuck is very simple to build. The five "V" sawbuck was designed with 10 vertical 1.2 m-long (4-foot) 2×4s, and four horizontal, 1.5 m-long (5-foot) 2×6s, secured with 89 mm (3.5 inches) wood screws. It was designed this way in order to cut two or more smaller pieces (0.6–1.2 m or 2–4 feet in length) of firewood in rapid succession. A sawbuck should be heavy enough to negate any kickback from the saw while cutting. Building a sawbuck that is too light could result in injury as it may tip over while cutting, especially with a chainsaw.
In Canada and Britain, but not in the United States, a sawbuck is called a sawhorse, although this term also refers to a similar device used (often in pairs) to support wood planks.
"Sawbuck" is also a slang term for a U.S. $10 bill, derived from the similarity between the shape of a sawbuck device and the Roman numeral X (10), which formerly appeared on $10 bills. A "double sawbuck" is a twenty dollar bill.