- any composite plant of the genus Dahlia, native to Mexico and Central America and widely cultivated for its showy, variously colored flower heads.
- the flower or tuberous root of a dahlia.
- a pale violet or amethyst color.
- of the color dahlia.
- any herbaceous perennial plant of the Mexican genus Dahlia, having showy flowers and tuberous roots, esp any horticultural variety derived from D. pinnata : family Asteraceae (composites)
- the flower or root of any of these plants
