What is the meaning of acknowledge?

verb

• Declare to be true or admit the existence or reality or truth of.
  • usage: "He admitted his errors"; "She acknowledged that she might have forgotten"
  • synonyms: admit
• Report the receipt of.
  • usage: "The program committee acknowledged the submission of the authors of the paper"
  • synonyms: receipt
• Express recognition of the presence or existence of, or acquaintance with.
  • usage: "He never acknowledges his colleagues when they run into him in the hallway"; "She acknowledged his complement with a smile"; "it is important to acknowledge the work of others in one's own writing"
  • synonyms: notice
• Express obligation, thanks, or gratitude for.
  • usage: "We must acknowledge the kindness she showed towards us"
  • synonyms: recognize, recognise
• Accept as legally binding and valid.
  • usage: "acknowledge the deed"
• Accept (someone) to be what is claimed or accept his power and authority.
  • usage: "The Crown Prince was acknowledged as the true heir to the throne"; "We do not recognize your gods"
  • synonyms: recognize, recognise, know