Synonyms for Garden Sorrel (same or very similar meaning)
WordNet sense 1 (low perennial with small silvery-green ovate to hastate leaves):
French sorrel, Rumex scutatusWordNet sense 2 (European sorrel with large slightly acidic sagittate leaves grown throughout north temperate zone for salad and spring greens):
sour dock, Rumex acetosaFrom the ODE community, based on WordNetadd/edit