Definitions of worker:

• noun:   sterile member of a colony of social insects that forages for food and cares for the larvae
• noun:   a person who works at a specific occupation

  Example: "He is a good worker"

• noun:   a person who acts and gets things done

  Example: "He's a miracle worker"

• noun:   a member of the working class (not necessarily employed)

  Example: "Workers of the world--unite!"

• name:  A surname (very rare: popularity rank in the U.S.: #30873)