gibbous vs unequal

gibbous

adj
  • Humpbacked. 

  • Characterized by convexity; protuberant. 

  • Having more than half (but not the whole) of its disc illuminated. 

unequal

adj
  • Out of balance. 

  • Not the same. 

  • Inadequate; insufficiently capable or qualified. 

  • Erratic, inconsistent. 

noun
  • One who is not an equal. 

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