What is the meaning of consolidate?

verb

• Unite into one.
  • usage: "The companies consolidated"
• Make firm or secure; strengthen.
  • usage: "consolidate one's gains"; "consolidate one's hold on first place"
• Bring together into a single whole or system.
  • usage: "The town and county schools are being consolidated"
• Form into a solid mass or whole.
  • usage: "The mud had consolidated overnight"
• Make or form into a solid or hardened mass.
  • usage: "consolidate fibers into boards"