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ach-laut

British  
/ ˈæx-, ˈæklaʊt /

noun

  1. (sometimes capital) phonetics the voiceless velar fricative sound that is written as ch in Scottish loch or in German ach, often allophonic with the ich-laut See also ich-laut

"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 ach-laut

from German, from ach ah + Laut sound