n. & v.
n. 1 a a whirring sound. b a rough sounding of the letter r. 2 (also bur) a a rough edge left on cut or punched metal or paper. b a surgeon's or dentist's small drill. 3 a a siliceous rock used for millstones. b a whetstone. 4 = BUR 1, 2. 5 the coronet of a deer's antler.
v. 1 tr. pronounce with a burr. 2 intr. speak indistinctly. 3 intr. make a whirring sound.
[ var. of BUR ]