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1726 (earlier petala, 1704), from Modern Latin petalum "petal" (17c.), from Greek petalon "a leaf; leaf of metal, thin plate," noun use of neuter of adj. petalos "outspread, broad, flat," from PIE root *pete- "to spread out" (see pace (n.)). Related: Petaline.
Moving toward: basipetal.
One of the often brightly colored parts of a flower surrounding the reproductive organs. Petals are attached to the receptacle underneath the carpels and stamens and may be separate or joined at their bases. As a group, the petals are called the corolla. See more at flower.