Synonyms for Imagination (same or very similar meaning)
WordNet sense 1 (the ability to form mental images of things or events):
imagery, imaging, mental imagery
WordNet sense 2 (the ability to deal resourcefully with unusual problems):
resource, resourcefulness
WordNet sense 3 (the formation of a mental image of something that is not perceived as real and is not present to the senses):
vision, imaginativeness
From the ODE community, based on WordNet
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