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third eye

third eye

9.8
A small part on top of the head in some reptiles that senses changes in light
  • noun
  • /θɜrd aɪ/
  • Specialized
translation icon : tercer ojo
  • In some reptiles, the third eye helps detect changes in light even when their eyes are closed.

Examples

  • Researchers have found that the third eye can react to light, similar to regular eyes.

  • The third eye on the top of a lizard's head allows it to sense predators from above.

  • When did she get the third eye removed?

  • A blue dot appears on her forehead like a third eye.

    Fiction book (2000)
  • You got that third eye right here," she tapped her forehead, "and you can see right down that narrow line.

    Fiction book (1993)
  • A clean bullethole has left him with a third eye, a bloody back, and an entourage of late summer flies.

    Fiction book (1993)
  • Ancient researchers gave this third eye a biological designation: the pineal gland.

    Blog text (12)

Synonyms

pineal eye
vsthird eye
  • Specialized
9.9

A small organ that senses light on top of the head in some lizards and other animals

is the same organ but described as detecting simple changes in light

Surface Forms

third eye singular
third eyes plural

Morphology

third + eye

The meaning 'a light-sensitive organ on the top of the head' is directly derivable from combining 'third' (ordinal number three) with 'eye' (a vision organ); a B1 learner who knows both words would infer an additional/extra eye. This composition is literal and cross-linguistically common, so the biological sense is immediately comprehensible (note: there is also a metaphoric 'third eye' sense, but that does not affect the compositional transparency of the biological meaning).

Etymology

Third eye comes from some reptiles that really have a small extra eye on the top of their head. This extra eye can 'detect changes in light' to help the animal know day from night, so the phrase means a light-sensitive organ.