noun

1. 1. the act or power of forming mental images of what is not actually present
   2. the act or power of creating mental images of what has never been actually experienced, or of creating new images or ideas by combining previous experiences; creative power
2. anything imagined; mental image; creation of the mind; fancy
3. a foolish notion; empty fancy
4. the ability to understand and appreciate imaginative creations of others, esp. works of art and literature
5. resourcefulness in dealing with new or unusual experiences
6. Obsolete an evil plan or scheme

Etymology: ME ymaginacioun < OFr imagination < L imaginatio < pp. of imaginari: see imagine