any of a genus (Helianthus) of tall plants of the composite family, having large, yellow, daisylike flowers with yellow, brown, purple, or almost black disks containing edible seeds that yield an oil
See sunflower in American Heritage Dictionary 4
noun
a. Any of several plants of the genus Helianthus, especially H. annuus, having tall coarse stems and large, yellow-rayed flower heads that produce edible seeds rich in oil.
b. The seedlike fruit or the seeds of this plant.
A brilliant yellow to strong or vivid orange yellow.