Bur
Part of speech: noun
Definition: A rough, prickly husk around the seeds or fruit of some plants. Any of several plants having such husks. A rotary cutting implement having a selection of variously shaped heads.
Burr
Part of speech: noun
Definition: A sharp, pointy object, such as a sliver or splinter.A bur; a seed pod with sharp features that stick in fur or clothing.A small piece of material left on an edge after a cutting operation.A rough humming sound.A rolled "r".A sharp, pointy object, such as a sliver or splinter.
Part of speech: verb
Definition: To pronounce with a rolled "r".To make a rough humming sound.