@Disguised22
Illusion, noun (Oxford Dictionary)
• A thing that is or is likely to be wrongly perceived or interpreted by the senses.
"the illusion makes parallel lines seem to diverge by placing them on a zigzag-striped background"
• A deceptive appearance or impression.
"the illusion of family togetherness"
• A false idea or belief.
"she had no illusions about the trouble she was in"
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(Merriam-Webster)
• 1a1: a misleading image presented to the vision
• 1a2: something that deceives or misleads intellectually
• 1b1: perception of something objectively existing in such a way as to cause misinterpretation of its actual nature
• 1b2: hallucination
• 1b3: a pattern capable of reversible perspective
• 2a1: the state or fact of being intellectually deceived or misled / misapprehension
• 2a2: an instance of such deception
• 2b: obsolete / the act of deceiving
• 3: a fine plain transparent bobbinet or tulle usually made of silk and used for veils, trimmings, and dresses.
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If you're looking for a word that implies incorporeality or intangibility, you might consider using
Mirage instead.