a plant, Medicago sativa, of the legume family, usually having bluish-purple flowers, originating in the Near East and widely cultivated as a forage crop.
al·fal·fa (āl-fāl'fə) n. A southwest Asian perennial herb (Medicago sativa) having compound leaves with three leaflets and clusters of usually blue-violet flowers. It is widely cultivated as a pasture and hay crop.
[Spanish, from Arabic al-faṣfaṣa : al-, the + faṣfaṣa, alfalfa (variant of fiṣfiṣa, from Persian aspist, clover).]