burr

noun

• 1a whirring sound, such as a telephone ringing tone or the sound of cogs turning.
• a rough pronunciation of the letter r, especially with a uvular trill as in a Northumberland accent.
• (loosely) a regional accent:a soft Scottish burr

• 2 (also bur) a rough edge or ridge left on an object (especially of metal) by the action of a tool or machine.

• 3 (also bur) a small rotary cutting tool with a shaped end, used chiefly in woodworking and dentistry.
• a small surgical drill for making holes in bone, especially in the skull.

• 4 [mass noun] a siliceous rock used for millstones.
• [count noun] a whetstone.

• 5 (also bur) a prickly seed case or flower head that clings to clothing and animal fur.
• [usually as modifier] a plant that produces burrs, for example bur-reed.

• 6 (also bur) [as modifier] denoting wood containing knots or other growths which show a pattern of dense swirls in the grain when sawn, used for veneers and other decorative woodwork:burr walnut

• 7the coronet of a deer’s antler.

verb

• 1 [no object] make a whirring sound.
• speak with a regional accent, especially one in which the letter r is prominent.

• 2 [with object] form a rough edge on (metal).