Webster's Revised Unabridged Dictionary · 1913

Petal

Petal (pet"al; 277) , noun

[Greek pe`talon a leaf, a leaf or plate of metal, from pe`talos outspread, broad, flat: compare French pétale. See Fathom.]

1.
(Botany) One of the leaves of the corolla, or the colored leaves of a flower. See Corolla, and Illust. of Flower.
2.
(Zoology) One of the expanded ambulacra which form a rosette on the black of certain Echini.