modified leaf. usually growing just below the flower petals. Sometimes more prominent than and mistaken for the actual flower petals (e.g.. in Comus spp.).
bract (Wikipedia)
In botany, a bract is a modified or specialized leaf, especially one associated with a reproductive structure such as a flower, inflorescence axis, or cone scale.
Bracts are usually different from foliage leaves; they may be of a different size, color, shape, or texture. Typically, they also look different from the parts of the flower, such as the petals or sepals.
A plant having bracts is referred to as bracteate or bracteolate, while one that lacks them is referred to as ebracteate or ebracteolate.