airlift vs ambulance

airlift

verb
  • To transport (troops etc) in an airlift. 

noun
  • The transportation of troops, civilians or supplies by air, especially in an emergency. 

  • Such a flight. 

  • A pipe that is used to suck up objects from the sea bed. 

ambulance

verb
  • To transport by ambulance. 

noun
  • A mobile field hospital. 

  • An emergency vehicle designed for transporting seriously ill or injured people to a hospital. 

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