What is the meaning of indenture?

noun

• A concave cut into a surface or edge (as in a coastline.
  • synonyms: indentation
• Formal agreement between the issuer of bonds and the bondholders as to terms of the debt.
• A contract binding one party into the service of another for a specified term.
• The space left between the margin and the start of an indented line.
  • synonyms: indentation, indention, indent

verb

• Bind by or as if by indentures, as of an apprentice or servant.
  • usage: "an indentured servant"
  • synonyms: indent