central vs coherent

central

adj
  • Exerting its action towards the peripheral organs. 

  • Having or containing the centre of something. 

  • Being in the centre. 

  • Being very important, or key to something. 

noun
  • centre 

coherent

adj
  • Attaching or pressing against an organ of the same nature. 

  • Of waves having the same direction, wavelength and phase, as light in a laser. 

  • Unified; sticking together; making up a whole. 

  • Belonging to a specific class of sheaves having particularly manageable properties closely linked to the geometrical properties of the underlying space. 

  • Orderly, logical and consistent. 

  • Aesthetically ordered. 

  • Having a natural or due agreement of parts; harmonious: a coherent design. 

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