burr / bər/ • n. 1. [in sing.] a rough sounding of the sound r, esp. with a uvular trill (a "French r") as in certain Northern England accents. ∎ (loosely) a regional accent charcterized by such a trill: a soft Scottish burr. 2. (also bur) a rough edge or ridge left on an object (esp. 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, medicine, and dentistry. 4. variant spelling of bur.