There are two definitions of an ambigram, which are the two sides of the same coin.

An ambigram is a typographic piece of art that has at least two ways of being read.

An ambigram is a typographic piece of art that remains readable after a transformation happens.

The core function of an ambigram is this:

• I read something
• Something happens
• I can read it again

The “something happens” part is a transformation and it constitutes the typology of the ambigram. There are three categories of ambigrams: geometric, mind and filter.

• If “something happens” to the art, we have a geometric ambigram.

• If “something happens” to the viewer’s mind, we have a mind ambigram.

• If “something happens” in between, we have a filter ambigram.

The hierarchy of the categories is illustrated in this diagram.

Definitions

Geometric ambigrams

A geometric ambigram is defined by two things: the transformation (rotation, reflection, translation, or multiple transformations) and the unit it is applied to. The unit is the part of the art that goes through the transformation. So far, we know three units: the whole word, the segments of a word (two or more), and each glyph separately. A type is a unit plus a transformation. For example, rotation applied to the whole word is a rotational ambigram, rotation applied to each segment is a segmental rotational ambigram, and rotation applied to each glyph is a rotatogram.

Rotational ambigram: A typographic design that rotates as a whole word to its center.
Sub-types: 180°, 120°,90°etc.

Reflective ambigram: A typographic design that reflects as a whole to its center.
Sub-types: mirror (vertical axis), lake (horizontal axis), diamond (diagonal axis).

Slidegram (or translation ambigram): A typographic design that translates (moves) as a whole out of the canvas boundary, while the disappearing part of the word appears on the opposite side.
Sub-types: horizontal, vertical, diagonal.

Multigram: A typographic design that uses multiple geometric transformations to the whole word.

Segmental rotational ambigram: A typographic design where the word is split into two or more segments, and each segment rotates to its own center.

Segmental reflective ambigram: A typographic design where the word is split into two or more segments, and each segment reflects to its own center.

Segmental slidegram: A typographic design where the word is split into two or more segments, and each segment translates within its own boundary, while the disappearing part of the segment appears on its opposide side.

No example yet.

Segmental multigram: A typographic design that uses multiple geometric transformations to each segment separately.

No example yet.

Rotatogram: A typographic design that uses rotation to each glyph separately.

Reflectogram: A typographic design that uses reflection to each glyph separately.

Slidogram: A typographic design that uses translation (movement) to each glyph separately.

Jumblegram: A typographic design that uses multiple geometric transformations in each glyph separately.

Mind ambigrams

A mind ambigram is defined by what happens in the viewer’s mind. The art itself stays exactly as it is. Nothing moves, nothing is added, and nothing is placed in front of it. The second reading appears because the viewer’s perception shifts: a letterform is read as another letter, the background becomes the subject, or a hidden cue is finally noticed. Each type below is a different way for the mind to make that switch. These mechanisms also serve as building blocks for the other categories, as the hierarchy diagram shows.

Middle-form (aka. perceptual shift or oscillation): A typographic design where a letterform can resemble two letters by taking their middle form.

Figure-ground: A typographic design in which both positive and negative space form words.

Containment: A typographic design in which a word is contained in a part of another word.

Arrangement: A typographic design in which the letters of a word are displayed in a way that the whole piece can be read in two or more ways.

Fill-the-gap: A typographic design in which parts of the letters are occluded so that the letters can be interpreted in two or more ways.

Hidden-cue: A typographic design in which a subtle visual hint, or “cue”, guides the viewer to discover a hidden second reading not immediately apparent.

Emphasis: A typographic design where certain letters of a word or phrase are emphasized so that they form a second word.

Stableshift: A typographic design where a letterform can resemble two letters by being displayed in an unstable position.

Multistable: A typographic design where a single letterform can be interpreted as multiple distinct letters, depending on the viewer’s perception.

Filter ambigrams

A filter ambigram is defined by something that happens between the art and the viewer. The art stays exactly as it is, and the viewer’s mind does no special work. Instead, a filter is placed between the two, and the second reading appears through it. The three types below differ by the kind of filter: blur softens the image, a solid object hides part of it, and a lens bends the light, which can even reflect, rotate, or shift the art, so a filter can deliver a geometric transformation.

Blur: A typographic design where the second read is visible when viewed through a blurry filter.

Solid: A typographic design where the second read is visible when a solid object is placed between the viewer and the art.

Lens: A typographic design where the second read is visible through a lens.