A biennial umbellifer (Apium graveolens var. dulce) of Mediterranean origin and belonging to the plant order Apiales. Celery is grown for its petioles or leafstalks, which are most commonly eaten as a salad but occasionally cooked as a vegetable (see illus.). Celeriac or knob celery (A. graveolens var. rapaceum) is grown for its enlarged rootlike stem and is commonly eaten as a cooked vegetable in Europe.