commissure vs juncture

commissure

noun
  • The line where the upper and lower lips or eyelids meet. 

  • A band of nerve tissue connecting the hemispheres of the brain, the two sides of the spinal cord, etc. 

  • The joint between two bones. 

juncture

noun
  • A place where things join, a junction. 

  • A critical moment in time. 

  • The manner of moving (transition) or mode of relationship between two consecutive sounds; a suprasegmental phonemic cue, by which a listener can distinguish between two otherwise identical sequences of sounds that have different meanings. 

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