spathe

A spathe is a large, often showy bract that encloses or surrounds a flower cluster, particularly the spadix of plants like calla lilies, anthuriums, and peace lilies.

What many people mistake for the flower's petal in these plants is actually the spathe—the true flowers are the tiny structures clustered on the central spike.

Spathes may be white, pink, red, or green depending on the species.