flatboat vs inflatable

flatboat

noun
  • A boxy, flat-bottomed boat used for carrying livestock, freight, and people on rivers. 

inflatable

noun
  • A boat or dinghy that may be inflated when needed. 

  • Any other structure, artwork etc. that is inflated. 

adj
  • Able to be inflated or blown up. 

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