What is the meaning of reinforcement?

noun

• A military operation (often involving new supplies of men and materiel) to strengthen a military force or aid in the performance of its mission.
  • usage: "they called for artillery support"
  • synonyms: support, reenforcement
• Information that makes more forcible or convincing.
  • usage: "his gestures provided eloquent reinforcement for his complaints"
  • synonyms: reenforcement
• Psychology) a stimulus that strengthens or weakens the behavior that produced it.
  • synonyms: reinforcing stimulus, reinforcer
• A device designed to provide additional strength.
  • usage: "the cardboard backing was just a strengthener"; "he used gummed reinforcements to hold the page in his notebook"
  • synonyms: strengthener
• An act performed to strengthen approved behavior.
  • synonyms: reward