billow vs puff up

billow

verb
  • To swell out or bulge. 

  • To surge or roll in billows. 

noun
  • A large wave, swell, surge, or undulating mass of something, such as water, smoke, fabric or sound 

puff up

verb
  • To swell due to injury or illness. 

  • To inflate with air. 

  • To become proud. (Often written as puffed up with pride.) 

  • To fluff up, such as an animal raising its fur or feathers to appear larger or conserve body heat. 

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