According to Wikipedia, the introduction of this term "is usually credited to the British phonetician Daniel Jones. In the first edition of the English Pronouncing Dictionary (1917), he named the accent 'Public School Pronunciation'; for the second edition in 1926 he [changed it to] Received Pronunciation." However (Wikipedia points out), "the term had been used much earlier by P. S. Du Ponceau in 1818 and the Oxford English Dictionary cites quotations back to about 1710. A similar term, 'received standard', was coined by Henry C. K. Wyld in 1927."
To paraphrase Wikipedia's next point: the terms 'received pronunciation' and 'received standard' have since been used interchangeably by linguists. I would suggest however that in informal contexts, 'received pronunciation' (or RP) is much more commonly used.
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