endangered vs uncommon

endangered

adj
  • in danger, at risk, said of something where there is a strong possibility something bad will happen to it (for example, a species in danger of going extinct) 

uncommon

adj
  • Rare; not readily found; unusual. 

  • Remarkable; exceptional. 

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