What is the meaning of endeavour?

noun

• A purposeful or industrious undertaking (especially one that requires effort or boldness. )
  • usage: "he had doubts about the whole enterprise"
  • synonyms: enterprise, endeavor
• Earnest and conscientious activity intended to do or accomplish something.
  • usage: "made an effort to cover all the reading material"; "wished him luck in his endeavor"; "she gave it a good try"
  • synonyms: attempt, effort, endeavor, try

verb

• Attempt by employing effort.
  • usage: "we endeavor to make our customers happy"
  • synonyms: endeavor, strive