harvestman vs old maid

harvestman

noun
  • An order of terrestrial, non-venomous arachnids with often very long legs: Opiliones. 

  • A field-worker who works to gather in the harvest. 

old maid

noun
  • The common zinnia. 

  • An unpopped kernel in a batch of popped popcorn kernels. 

  • The Madagascar periwinkle. 

  • The unmatchable card in that game. 

  • An old woman who has never married; a spinster. 

  • A card game in which cards must be paired and one undesirable card is designated "old maid". 

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