The following was sent to me as part of an email that advertised for a book about the Constitution...
Q37. "Send 20 FRNs [Federal Reserve Notes, commonly but erroneously called dollars - see the Coinage Act of 1792. A dollar is defined by law as 371.25 grains of fine silver]."
A. I was curious about this, so I looked it up. According to the U.S. Code: "United States money is expressed in dollars" (31 USC 5101). The term "dollar" is used twice in the Constitution: once in Article 1, Section 9 when referring to a slave tax (no more than 10 dollars per head) and once in the 7th Amendment - the U.S. Code is essentially putting into law what can be inferred from the Constitution. A dollar coin, by law, is defined as: "a dollar coin that is 1.043 inches in diameter and weighs 8.1 grams" (31 USC 5112(a1)). So, I think the way it works is that a federal reserve note is just another way of saying "dollar," historical definitions and superseded law not withstanding.
Do you accept checks with "dollars" pre-printed on them?