insignificant vs neglectable

insignificant

adj
  • Not significant; not important, inconsequential, or having no noticeable effect. 

  • Without meaning; not signifying anything. 

neglectable

adj
  • Small enough or unimportant enough to be neglected; negligible. 

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