closing vs onset

closing

noun
  • In morphology, the erosion of the dilation of a set. 

  • The final procedure in a house sale, when documents are signed and recorded. 

  • The act by which something is closed. 

  • The end or conclusion of something. 

adj
  • Pertaining to the finish or ending of a series of events; occurring at the end or after all others. 

onset

noun
  • The initial portion of a syllable, preceding the syllable nucleus. 

  • The beginning of a musical note or other sound, in which the amplitude rises from zero to an initial peak. 

  • The initial phase of a disease or condition, in which symptoms first become apparent. 

  • A setting about; a beginning. 

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