assignee vs worker

assignee

noun
  • one who is appointed to act or speak in place of another; an agent 

  • one to whom rights or property is being transferred 

  • one to whom a thing is assigned 

worker

noun
  • A person who performs labor for a living, especially manual labor. 

  • A nonreproductive social insect, such as ant, bee, termite, or wasp. 

  • A female ant, bee, termite or wasp. 

  • A thread performing one instance of a particular task within a program. 

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