coracle vs waka

coracle

noun
  • A small circular or oblong boat made of wickerwork and made watertight with hides or pitch, propelled and steered with a single paddle and light enough to be carried on a person's back. 

waka

noun
  • A Maori canoe. 

  • A kind of classical Japanese poem. 

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