meter vs metre

meter

noun
  • The base unit of length in the International System of Units (SI), conceived as 1/10,000,000 of the distance from the North Pole to the Equator, and now defined as the distance light will travel in a vacuum in 1/299,792,458 seconds. 

  • A parking meter or similar device for collecting payment. 

  • A line above or below a hanging net, to which the net is attached in order to strengthen it. 

  • The overall rhythm of a song or poem; particularly, the number of beats in a measure or syllables in a line. 

verb
  • To regulate the flow of or to deliver in regulated amounts (usually of fluids but sometimes of other things such as anticipation or breath). 

  • To imprint a postage mark with a postage meter. 

  • To measure with a metering device. 

metre

noun
  • 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. 

  • The rhythm or measure in verse and musical composition. 

verb
  • To put into metrical form. 

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