What is the meaning of unitary?

adjective

• Relating to or characterized by or aiming toward unity.
  • usage: "the unitary principles of nationalism"; "a unitary movement in politics"
• Of or pertaining to or involving the use of units.
  • usage: "a unitary method was applied"; "established a unitary distance on which to base subsequent calculations"
• Characterized by or constituting a form of government in which power is held by one central authority.
  • usage: "a unitary as opposed to a federal form of government"
• Having the indivisible character of a unit.
  • usage: "a unitary action"; "spoke with one voice"
  • synonyms: one