harmless vs ominous

harmless

adj
  • Incapable of causing harm or danger; safe. 

  • Not intended to harm; inoffensive. 

ominous

adj
  • Specifically, giving indication of a coming ill; being an evil omen 

  • Of or pertaining to an omen or to omens; being or exhibiting an omen; significant. 

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