sign over vs taxi

sign over

verb
  • To transfer (property or rights) to somebody else by signing a document. 

taxi

noun
  • A vehicle that may be hired for single journeys by members of the public, driven by a taxi driver. 

  • A share taxi. 

  • The movement of an aircraft across an airport's surface under its own power; a phase of aircraft operation involving this movement. 

verb
  • To move an aircraft on the ground under its own power. 

  • To travel by taxicab. 

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