One of the mysteries of the English language finally explained.
In representations or imitation of upper or upper-middle-class speech (originally that of ‘Sloane Rangers’): yes. Also as noun: an utterance of this.
Of, relating to, or designating a person who is conspicuously or unselfconsciously upper or upper-middle-class in speech; ‘posh’, ‘Sloanie’.
1980s; earliest use found in The Times. From OK [interjection¹, noun², adverb] + yah.
OK yah/ˌəʊkeɪ ˈjɑː/
In this article we explore how to impress employers with a spot-on CV.