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half-jack

British  

noun

  1. informal  a flat pocket-sized bottle of alcohol

"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 half-jack

C20: jack, probably from C16 jack a leather-covered vessel, from Old French jaque, of uncertain origin

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.

Nine Bristol barques were lying off Three Towns, a place not upon the chart, and at Half-Jack, 205 miles from the Cape.

From Project Gutenberg