Allusion or Illusion?

by Craig Shrives

What Is the Difference between "Allusion" and "Illusion"?

"Allusion" and "illusion" are easy to confuse because they sound similar.
  • "Allusion" is an indirect reference to something.
    • In his speech, Toby made an allusion to his own work. correct tick
    • (This means that Toby didn't talk about his own work directly but referred to it indirectly.)
  • "Illusion" is a false impression.
    • It's not an oasis but an illusion. correct tick

More about "Allusion" and "Illusion"

The nouns "allusion" and "illusion" sound quite similar, and they both have connotations of intangibility. As a result, they are sometimes confused by writers.


The noun "allusion" denotes a subtle or indirect reference to something (i.e., a hint at something). It derives from the verb "to allude."

Example sentences with "allusion":
  • The Simpsons is full of allusions to well-known films. correct tick
  • His consistent allusions to being so poor as a child are not in keeping with his brother's version of their childhood. correct tick
  • His statement was an obvious allusion to your complaint. correct tick
  • We must quote whenever we feel that the allusion is interesting, helpful, or amusing. correct tick (Author Clifton Fadiman)
Read also about "allude" and "elude."


"An illusion" is a false impression or deception.

Example sentences with "illusion":
  • The greatest obstacle to discovery is not ignorance - it is the illusion of knowledge. (Historian Daniel J. Boorstin)
  • It gives the illusion of floating in space. correct tick
  • Love can be magic, but magic can just be an illusion. correct tick (Noah's grandson Javan)
allusion or illusion difference

"Under No Illusion" or "Under No Allusion"?

The term "under no illusion" or "under no illusions" means "to be fully aware of the situation." ("To be under no allusion" is wrong.)

Example sentences with "under no illusion":
  • I am under no illusion how much work is required. correct tick
  • (This means "I fully understand how much work is required.")
  • I'm under no illusion that there are things about me that I'd like to change. I just accept who I am, and I'm proud of it. correct tick (Singer Paloma Faith)

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