WordNet sense 1 (any of various plants of the genus Zinnia cultivated for their variously and brightly colored flower heads):

zinnia, old maid flower

WordNet sense 2 (commonly cultivated Old World woody herb having large pinkish to red flowers):

periwinkle, Cape periwinkle, Catharanthus roseus, cayenne jasmine, Madagascar periwinkle, red periwinkle, rose periwinkle, Vinca rosea

WordNet sense 3 (an elderly unmarried woman):

spinster