Definition of dicotyledon
- a flowering plant with an embryo that bears two cotyledons (seed leaves). Dicotyledons constitute the larger of the two great divisions of flowering plants, and typically have broad stalked leaves with net-like veins (e.g. daisies, hawthorns, oaks). Compare with monocotyledon.
- Class Dicotyledoneae (or -donae, -dones; sometimes Magnoliopsida), subdivision Angiospermae
early 18th century: from modern Latin dicotyledones (plural), from di- 'two' + cotyledon (see cotyledon)