onset vs termination

onset

noun
  • A setting about; a beginning. 

  • 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. 

termination

noun
  • An end in space; an edge or limit. 

  • The last part of a word; an ending, a desinence; a suffix. 

  • An induced abortion. 

  • The process of firing an employee; ending one's employment at a business for any reason. 

  • An end in time; a conclusion. 

  • An outcome or result. 

  • The ending up of a polypeptid chain. 

  • The process of terminating or the state of being terminated. 

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