Any rough or prickly envelope of the seeds of plants, whether a pericarp, a persistent calyx, or an involucre, as of the chestnut and burdock. Also, any weed which bears burs.
- A rough prickly husk or covering surrounding the seeds or fruits of plants such as the chestnut or the burdock.
- A plant producing such husks or coverings.
- A persistently clinging or nettlesome person or thing.
- A rough protuberance, especially a burl on a tree.
- Any of various rotary cutting tools designed to be attached to a drill.
- Variant of burr2.
- Variant of burr3.