haplography vs syncope

haplography

noun
  • Accidental omission of a letter or letter group that should be repeated in writing, for example, mispell for misspell. 

syncope

noun
  • The loss or elision of a sound, from the interior of a word, especially of a vowel sound with loss of a syllable. 

  • A loss of consciousness when someone faints. 

  • A missed beat or off-beat stress in music resulting in syncopation. 

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