- dahlia [dal′yə, däl′yə; ] chiefly Brit [ dāl′yə]n.[ModL, after A. Dahl, 18th-c. Swed botanist]1. any of a genus (Dahlia) of perennial plants of the composite family, with tuberous roots and large, showy flower heads in various bright colors, native to Mexico and Central America2. the flower of this plant
English World dictionary. V. Neufeldt. 2014.