marsh marigold: swamp plant of Europe and North America having bright yellow flowers resembling buttercups
entity: that which is perceived or known or inferred to have its own distinct existence (living or nonliving)
phase iii clinical trial: a large clinical trial of a treatment or drug that in phase I and phase II has been shown to be efficacious with tolerable side effects; after successful conclusion of these clinical trials it will receive formal approval from the FDA