As noted in these pages and elsewhere, a debate is under way in Washington over the Consumer Price Index and whether it has been accurately gauging the rise in the U.S. cost of living or has been overestimating the pace of that rise. It is a highly charged debate -- billions of dollars in government checks to ordinary Americans ride on the outcome -- and politicians are understandably torn between wanting to pass the buck and trying to get enough bang for the buck.
As the preferred slang term for what Washington Irving called "the almighty dollar," buck in all likelihood sprang from buck skin or buck hide -- a commodity of exchange, and metaphorically a loose measure of value, in Colonial trade with Native Americans. ("He has been robbed of the value of 300 Bucks, & you all know by whom" -- this 1748 quotation comes from the Ohio River Valley, and is cited in Mitford M. Mathews's .) The earliest undisputed example of buck in the precise sense of "dollar" ("mulcted for the sum of twenty bucks") has a Sacramento provenance, and dates back only to Gold Rush times. Although the Forty-niners may well have popularized this new sense, traders at outposts east of the Continental Divide were probably already using it; the scanty written records of vernacular speech of the time preclude certainty. Unlisted in early slang dictionaries, buck seems not to have gained national popularity until the 1890s -- a good example of the slow dissemination of slang in the days before radio, television, and the Internet.
Also from the mid nineteenth century comes sawbuck, a term synonymous with "sawhorse," whose connection with the meaning "$10 bill" was provided by the Roman numeral X that used to appear on $10 notes. The X apparently called to mind the crossed wooden supports of the sawyer's sawhorse, on which logs were cut with a bucksaw -- no pun intended. These bills were sometimes also called just Xs before the Civil War -- when a dollar was a dollar, a sawbuck had many times its 1990s purchasing power, and $10 bills must have been a comparatively impressive sight. More impressive still was the C-note, or $100 bill, C being the Roman numeral for 100. A five-dollar bill was, of course, a V. From the Yiddish finef or finf, meaning "five," comes another word for a five-spot: the fin of poker players and middle-aged cabbies.