Dialectal for ‘yea’ or ‘yes’; or in representations of Ger. or Du. speech. Cf. the earlier YAW adv.
1889. Rider Haggard, Allan’s Wife, iv. ‘Yah! yah! hold a light,’ put in one of the Boers.
1899. Daily News, 5 April, 5/1. ‘Yah,’ which the rustics of the Peak frequently use for ‘Yes,’ and which they employed exclusively thirty years ago. Ibid. (1905), 23 May, 4/7. America … has two substitutes for ‘yes.’ One of them is ‘yep’ and the other is ‘yah.’
