corolla

Etymology

From Latin corōlla (“small garland, chaplet or wreath”), diminutive of corōna (“garland, chaplet, wreath”).

noun

1. (botany) An outermost-but-one whorl of a flower, composed of petals, when it is not the same in appearance as the outermost whorl (the calyx); it usually comprises the petal, which may be fused.
   Our wet fingers touched and we formed a circle like the corolla of a flower, floating into the silence of the desert dawn with the ancient sun on our bodies. 1974, Lawrence Durrell, Monsieur, Faber & Faber, published 1992, page 125