aeroplane vs martin

aeroplane

noun
  • Any of various nymphalid butterflies, of various genera, having a slow gliding flight. Also called planes. 

  • Synonym of airplane. A powered heavier-than-air aircraft with fixed wings. 

verb
  • To fly in an aeroplane. 

  • To transport by aeroplane. 

martin

noun
  • Any of various passerine birds of the family Hirundinidae, which also includes swallows, that catch insects whilst flying. 

  • A perforated stone-faced runner for grinding. 

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