Pet"al (?), n. [Gr. a leaf, a leaf or plate of metal, fr. outspread, broad, flat: cf. F. p'etale. See Fathom.]
One of the leaves of the corolla, or the colored leaves of a flower. See Corolla, and Illust. of Flower.
One of the expanded ambulacra which form a rosette on the black of certain Echini.
© Webster 1913.