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sawbuck

1 American  
[saw-buhk] / ˈsɔˌbʌk /

noun

  1. a sawhorse.


sawbuck 2 American  
[saw-buhk] / ˈsɔˌbʌk /

noun

Slang.
  1. a ten-dollar bill.


sawbuck British  
/ ˈsɔːˌbʌk /

noun

  1. a sawhorse, esp one having an X-shaped supporting structure

  2. slang a ten-dollar bill

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of sawbuck1

1860–65, compare Dutch zaagbok

Origin of sawbuck2

1840–50, so called from the resemblance of the Roman numeral X to the crossbars of a sawbuck 1