What is the meaning of notion?

noun

• A vague idea in which some confidence is placed.
  • usage: "his impression of her was favorable"; "what are your feelings about the crisis"; "it strengthened my belief in his sincerity"; "I had a feeling that she was lying"
  • synonyms: impression, feeling, belief, opinion
• A general inclusive concept.
• An odd or fanciful or capricious idea.
  • usage: "the theatrical notion of disguise is associated with disaster in his stories"; "he had a whimsy about flying to the moon"; "whimsy can be humorous to someone with time to enjoy it"
  • synonyms: whim, whimsy, whimsey
• Usually plural. ( small personal articles or clothing or sewing items)
  • usage: "buttons and needles are notions"