aeroplane vs aircraft

aeroplane

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

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

verb
  • To fly in an aeroplane. 

  • To transport by aeroplane. 

aircraft

noun
  • A vehicle capable of atmospheric flight due to interaction with the air, such as buoyancy or lift 

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