What is the meaning of weaken?

verb

• Lessen the strength of.
  • usage: "The fever weakened his body"
• Become weaker.
  • usage: "The prisoner's resistance weakened after seven days"
• Destroy property or hinder normal operations.
  • usage: "The Resistance sabotaged railroad operations during the war"
  • synonyms: sabotage, undermine, countermine, counteract, subvert
• Reduce the level or intensity or size or scope of.
  • usage: "de-escalate a crisis"
  • synonyms: de-escalate, step down
• Lessen in force or effect.
  • usage: "soften a shock"; "break a fall"
  • synonyms: dampen, damp, soften, break