knoll vs mons

knoll

noun
  • A small mound or rounded hill. 

  • A rounded, underwater hill with a prominence of less than 1,000 metres, which does not breach the water's surface. 

  • A knell. 

verb
  • To ring (a bell) mournfully; to knell. 

  • To sound (something) like a bell; to knell. 

  • To call (someone, to church) by sounding or making a knell (as a bell, a trumpet, etc). 

  • To arrange related objects in parallel or at 90 degree angles. 

mons

noun
  • A mountain or extinct volcano on a planet or a moon. 

  • The pubic mound or mons pubis. In human anatomy or in mammals in general, the mons pubis (Latin for "pubic mound"), also known as the mons veneris (Latin, mound of Venus) or simply the mons, is the adipose tissue lying above the pubic bone of adult females, anterior to the pubic symphysis. The mons pubis forms the anterior portion of the vulva. 

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