keynote vs metre

keynote

noun
  • The note on which a musical key is based; the tonic. 

  • The main theme of a speech, a written work, or a conference. 

  • A speech that sets the main theme of a conference or other gathering; a keynote speech or keynote address. 

verb
  • To deliver a speech that sets the main theme of a conference or other gathering. 

metre

noun
  • The rhythm or measure in verse and musical composition. 

  • The basic unit of length in the International System of Units (SI: Système International d'Unités), equal to the distance travelled by light in a vacuum in 1/299 792 458 seconds. The metre is equal to 39+⁴⁷⁄₁₂₇ (approximately 39.37) imperial inches. 

verb
  • To put into metrical form. 

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