ambigram

     

An ambigram, also sometimes known as an inversion, is a graphical figure that spells out a wor not only in its form as presented, but also in another direction or orientation. The text can also consist of a few words, and the text spelled out in the other direction or orientation is often the same, but can also be a different text. Douglas R. Hofstadter describes an ambigram as a "calligraphic design that manages to squeeze two different readings into the selfsame set of curves."

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