apocope vs syncopation

apocope

noun
  • The loss or omission of a sound or syllable from the end of a word. 

  • The loss or omission of the last vowel in a word, together with any consonants that follow it. 

syncopation

noun
  • The contraction of a word by means of loss or omission of sounds or syllables in the middle thereof. 

  • The quality of a rhythm being somehow unexpected, in that it deviates from the strict succession of regularly spaced strong and weak beats in a meter. 

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