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blotto

American  
[blot-oh] / ˈblɒt oʊ /

adjective

Slang.
  1. very drunk; so drunk as to be unconscious or not know what one is doing.


blotto British  
/ ˈblɒtəʊ /

adjective

  1. slang unconscious, esp through drunkenness

"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 blotto

1915–20; blot 1 (v.) + -o