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oncer

British  
/ ˈwʌnsə /

noun

  1. (formerly) a one-pound note

  2. a person elected to Parliament who can only expect to serve one term

  3. something that happens on only one occasion

"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 oncer

C20: from once

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

The Labour tribe will respond by lobbying for a reissued oncer portraying Wilson, above the strapline "the pound in your pocket".

From The Guardian