What is the origin of the slang term for money sawbuck?

The slang term "sawbuck" for money originates from the term for a sawbuck, a wooden frame used to hold lumber while it is being cut. The name comes from the Roman numeral "X," which resembles the shape of the frame and also symbolizes ten dollars. This connection likely arose in the 19th century when "sawbuck" began to be used informally to refer to a ten-dollar bill.