burred, burring Definition

burr¹
noun

1. In some accents of English, such as that found in Northumberland: a rough ‘r' sound pronounced at the back of the throat.
2. A continual humming sound made eg by a machine.
3. A rough edge on metal or paper.
4. A small rotary drill used by a dentist or surgeon.

verb burred, burring

intr
1. To make a burring sound.
2. To pronounce something with a burr.

Etymology: 17c in sense 3; associated with bur, but perhaps also an imitation of the sound.