holograph vs siggy

holograph

noun
  • A handwritten document that is solely the work of the person whose signature it bears, especially a letter, deed, or will; an original manuscript, a protograph. 

  • A hologram. 

verb
  • To record by means of holography. 

siggy

noun
  • A sig (signature used in posted messages). 

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