higher vs servile

higher

verb
  • To make higher; to raise or increase in amount or quantity. 

  • To ascend. 

noun
  • A national school-leaving examination and university entrance qualification. 

servile

adj
  • Of or pertaining to a slave. 

  • Not belonging to the original root. 

  • Slavish or submissive. 

  • Not sounded, but serving to lengthen the preceding vowel, like the e in tune. 

noun
  • A slave; a menial. 

  • An element which forms no part of the original root. 

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