An ambigram is a typographical design which can be read in more than one way. There are many kinds of ambigrams, here are just a couple:
Rotation: An ambigram that can be read when rotated, usually 180 degrees.
Reflection: An ambigram that can be read when viewed in a mirror.
Figure-Ground: An ambigram where the negative space created by one word spells out another.
Ambigrams that say one thing one way, and something else another way may be called “symbiotograms.” Ambigrams that occur with using unaltered typography may be called “natural ambigrams.” Example: “pod” is a natural rotation ambigram. “mom” and “wow” is a natural rotation symbiotogram. “mom” is also a natural reflection ambigram. It’s possible to combine different types of ambigrams, and there are several types that aren’t listed above.
There’s a whole lot more to ambigrams than that, but that should give you the general idea.
As I design more ambigrams, I plan on sharing some of the tricks I come across so keep a look out for more posts! And now that you know what they are, go and request an ambigram for me to make!
If you’re interested in learning more about ambigrams from the masters, check out the following books: