Rumex crispus, the curly dock, curled dock or yellow dock, is a perennial flowering plant in the family Polygonaceae, native to Europe and Western Asia.
The plant produces an inflorescence or flower stalk that grows to about 1m high. It has smooth leaves shooting off from a large basal rosette, with distinctive waved or curled edges. On the stalk flowers and seeds are produced in clusters on branched stems, with the largest cluster being found at the apex. The seeds are shiny, brown and encased in the calyx of the flower that produced them.