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definitions

yah

[yah, yai]
interjection
  1. an exclamation of impatience or derision.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for yah

yah

sentence substitute
  1. an informal word for yes, often used to indicate derision or contempt
interjection
  1. an exclamation of derision or disgust

Yah

noun
  1. British informal an affected upper-class person

Word Origin for Yah

C20: from yah, the spoken form of yes supposedly used by upper-class British people
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
Word Origin and History for yah

exclamation of defiance or dismissal, from 1812.

Online Etymology Dictionary, © 2010 Douglas Harper