What is the meaning of imagination?

noun

• The formation of a mental image of something that is not perceived as real and is not present to the senses.
  • usage: "popular imagination created a world of demons"; "imagination reveals what the world could be"
  • synonyms: imaginativeness, vision
• The ability to form mental images of things or events.
  • usage: "he could still hear her in his imagination"
  • synonyms: imaging, imagery, mental imagery
• The ability to deal resourcefully with unusual problems.
  • usage: "a man of resource"
  • synonyms: resource, resourcefulness