Lappule

Lappule is a term that refers to a small, often sticky burr or seed pod, typically from plants of the burdock family (Arctium). These burrs are characterized by their hooked or spiny outer surface, which allows them to easily attach to the fur of animals, clothing, or other surfaces. This dispersal mechanism is a common adaptation in many plant species, helping them to spread their seeds over a wide area.

The word "lappule" is sometimes used interchangeably with "burr" or "cleaver," though it can sometimes imply a smaller size or a specific type of hooked seed casing. The sticky nature of lappules is due to the presence of tiny, stiff hooks that grip onto fibrous materials. In some contexts, the term might also be used informally to describe any small, clinging object that is difficult to remove. The ability of lappules to adhere so effectively has even inspired biomimicry, such as the invention of Velcro, which mimics the hook-and-loop system found in nature.