impressive vs insignificant

impressive

adj
  • Appealing. 

  • Capable of being impressed. 

  • Making, or tending to make, a positive impression; having power to impress 

insignificant

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

  • Without meaning; not signifying anything. 

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