What is the meaning of replacement?

noun

• The act of furnishing an equivalent person or thing in the place of another.
  • usage: "replacing the star will not be easy"
  • synonyms: replacing
• Someone who takes the place of another person.
  • synonyms: surrogate, alternate
• An event in which one thing is substituted for another.
  • usage: "the replacement of lost blood by a transfusion of donor blood"
  • synonyms: substitution, permutation, transposition, switch
• A person or thing that takes or can take the place of another.
  • synonyms: substitute
• Filling again by supplying what has been used up.
  • synonyms: refilling, replenishment, renewal
• A person who follows next in order.
  • usage: "he was President Lincoln's successor"
  • synonyms: successor