dragonfly vs odonate

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. 

odonate

noun
  • Any carnivorous insect of the order Odonata; a dragonfly or damselfly. 

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