burrs

noun

1. 1.A tree growth in which the grain has grown in a deformed manner.
2. 2.Wood of a mottled veneer, usually cut from such a growth.
3. 3.A knot or lump in thread or cloth.
4. 4.A sharp, pointy object, such as a sliver or splinter.
5. 5.A bur; a seed pod with sharp features that stick in fur or clothing.