Ambigram, a word coined by Douglas Hofstadter, refers to a piece of text which can be read in (at least) two different ways. Ambigrams can be built on three different principles: rotation, reflection, and oscillation.
Here’s an example of a rotational ambigram — the word cyclops in Greek. It reads the same right side up and upside down.
It’s also possible to make an asymmetrical rotational ambigram, which reads as a different word when inverted. For example, this tarot card includes a French ambigram which reads Pendu (“hanged man”) upright and Danse (“dance”) inverted.
Another kind of rotational ambigram uses a 90-degree rotation, so the text can be read either vertically or horizontally.
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