commensurable vs proportional

commensurable

adj
  • Related in size or scale; commensurate or proportionate. 

  • (of two or more numbers) Divisible by the same number ᵂᴾ 

  • Able to be measured using a common standard. 

proportional

adj
  • In proportion (to), proportionate. 

  • Of a typeface, having characters with natural (non-uniform) width (in contrast to monospace typefaces). 

  • At a constant ratio (to). Two magnitudes (numbers) are said to be proportional if the second varies in a direct relation arithmetically to the first. Symbol: ∝. 

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