initials vs squiggle

initials

noun
  • An abbreviation of a person's name, constructed by taking the initial letters of first, last, and sometimes middle name(s). See monogram 

squiggle

noun
  • Synonym of tilde. 

  • A short twisting or wiggling line or mark. 

  • An illegible scrawl. 

verb
  • To write illegibly. 

  • To make a squiggle. 

  • To wriggle or squirm. 

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