rajah vs rex

rajah

noun
  • a Hindu prince or ruler in India. 

  • Any of various nymphalid butterflies of the genus Charaxes. 

rex

noun
  • An animal which has a genetic recessive variation that causes the guard hairs to be very short or fully lacking. 

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