Definition - A rough sounding of the letter r.

1. According to the OED, it is specifically "the rough uvular trill … characteristic of the county of Northumberland, and found elsewhere as an individual peculiarity. (Writers ignorant of phonology often confuse the Northumberland burr with the entirely different Scotch r, which is a lingual trill…)"

Etymology -
The term's derivation in this sense is unknown. However, some claim that it was coined in imitation of the speech style itself; others claim that it derives from the phrase "to have a bur in your throat."

Oxford English Dictionary -
Its first citation is from 1760:
"An Aunt just come from the North, with the true NewCastle bur in her throat."
(Foote Minor (1781) Introd. 9)

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