threeeyed

Threeeyed is a term used to describe something that has or appears to have three eyes, or three eye-like sensory organs. It can function as an adjective and, in some contexts, as a proper name in fiction or branding. The concept is encountered in biology, folklore, and popular culture, where it is often used to indicate enhanced perception, mutated form, or otherworldliness.

In biology, a true third eye is referred to as a parietal eye. This photoreceptive organ occurs in some non-mammalian species as part of the pineal complex. It is typically not used for detailed vision and is often vestigial in adults, though it can play a role in circadian rhythms and hormonal regulation in certain species. The parietal eye is most commonly discussed in relation to reptiles such as lizards and the tuatara, where an embryonic or rudimentary third eye may be present.

In popular culture, three-eyed beings appear frequently as motifs for mutation or heightened awareness. Notable examples include Blinky, the three-eyed fish from The Simpsons, created as social commentary on pollution; and the Three-Eyed Raven in the literature and television adaptation A Song of Ice and Fire / Game of Thrones, depicted as a figure with prophetic insight. Beyond these, the trope appears in science fiction and fantasy to convey alienness, enhanced perception, or visionary abilities.

The term threeeyed is thus used across scientific and cultural contexts to denote an organism or character with an extra eye, often signaling unusual biology or symbolic meaning. See also parietal eye and related three-eyed depictions in media.