False description of the Tower of Pisa (6)

I believe the answer is:

untrue

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'false' is the definition.
(I know that false can be written as untrue)

I don't understand how the rest of the clue works.

Can you help me to learn more?

(Other definitions for untrue that I've seen before include "Not in accordance with fact" , "Counter-factual" , "Not factual or honest" , "Spurious" , "Fallacious" .)

I've seen this clue in The Globe and Mail.

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