cellar spider vs dragonfly

cellar spider

noun
  • Pholcus phalangioides, a spider of the family Pholcidae. 

dragonfly

noun
  • An insect of the suborder Epiprocta or, more strictly, the infraorder Anisoptera, having four long transparent wings held perpendicular to a long body when perched. 

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