What is the meaning of policy?

noun

• A plan of action adopted by an individual or social group.
  • usage: "it was a policy of retribution"; "a politician keeps changing his policies"
• A line of argument rationalizing the course of action of a government.
  • usage: "they debated the policy or impolicy of the proposed legislation"
• Written contract or certificate of insurance.
  • usage: "you should have read the small print on your policy"
  • synonyms: insurance policy, insurance