ˈ ̷ ̷ ̷ ̷ˌ ̷ ̷ noun
Etymology: yellow (I) + top
1.
a. : any of several goldenrods ; especially : early goldenrod — sometimes plural but sing. in constr.
b. : bitter clover
c. : golden crownbeard
2. : any of several plant diseases characterized by yellowing of the upper foliage: as
a. : a disease of alfalfa of undetermined cause characterized by a pronounced yellowing of the upper portions of affected plants
b. : a yellowing of alfalfa tops caused by the punctures of the potato leafhopper