ambrosia vs bitterweed

ambrosia

noun
  • Any fungus of a number of species that insects such as ambrosia beetles carry as symbionts, "farming" them on poor-quality food such as wood, where they grow, providing food for the insect. 

  • A dessert made of shredded coconuts and tropical fruits such as pineapples and oranges; some recipes also include ingredients such as marshmallow and cream. 

  • Any food with an especially delicious flavour or fragrance. 

  • Anything delightfully sweet and pleasing. 

  • The anointing-oil of the gods. 

  • The food of the gods, thought to confer immortality. 

  • A mixture of nectar and pollen prepared by worker bees and fed to larvae. 

  • An annual herb historically used medicinally and in cooking, Dysphania botrys. 

bitterweed

noun
  • Any plant in the genus Ambrosia, especially Ambrosia artemisiifolia (common ragweed). 

  • The plant Helenium amarum (yellow sneezeweed). 

  • Parthenium hysterophorus (false ragweed) 

  • Picris rhagadioloides (syn. Picris sprengeriana; tall oxtongue) 

  • Artemisia tripartita subsp. tripartita (syn. Artemisia trifida; threetip sagebrush) 

  • Tetraneuris spp. 

How often have the words ambrosia and bitterweed occurred in a corpus of books? (source: Google Ngram Viewer )