op-, opt-, optico-, opsi-, opso-, -opia, -ops, -opsia, -opsis, -opsy, -optic, -opic, -opy

(Greek: eye[s]; sight; see, vision)

panopticon (s), panopticons (pl) (noun forms)
1. A building; such as, a prison, a hospital, a library, etc., arranged so that all parts of the interior are visible from a single position.
2. A circular prison with cells distributed around a central surveillance station.
3. Movie theaters that deliver all kinds of entertainment and instructional programs, by transmitting virtual reality directly to the sensory systems of spectators, including odors, movement sensation, etc.
phonopsia
A condition in which the hearing of certain sounds gives rise to a subjective sensation of color or the condition of eliciting color sensations by acoustic stimulation; also synesthesia.
photopia, photopic, photopic vision
1. Relating to vision with the normal eyes in bright light; for example, day vision.
2. Pertaining to vision in the light; said of the eyes which have become light-adapted.
3. Sometimes applicable to seeing what appears to be sparks in front of the eyes.

A person can recognize the transition from photopic vision to scotopic (night) vision with the disappearance of color perception, which is replaced by shades of black and white.

photopsia, photopsy
An appearance as of sparks, or flashes, resulting from retinal irritation.
phototopia
Vision with eyes that are adapted to normal bright daylight.
Poem: Thanatopsis by William Cullen Bryant
A poet who is expressing his thoughts about death which is the fate of every human being.
polyopia
The formation of more than one image of an object on the retina; multiple vision.
presbyopia, presbyopic; presbytia, presbytic, presbytism
1. A form of farsightedness occurring after middle age, caused by a diminished elasticity of the crystalline lens.
2. The physiological loss of accommodation in the eyes in advancing age, said to begin when the near point has receded beyond 22 cm (9 inches).
3. The loss of the eye's ability to change focus to see near objects.
4. Eyesight characteristic of older people.

The reasons for this loss of the power of accommodation are not yet fully known. It is conventionally said to be a result of the lenses of the eyes becoming less elastic with time.

Presbyopia is associated with aging; however, it happens with everyone. The first sign is often the necessity to hold reading material farther away in order to be able to focus on the contents.

The term presbyopia is said to come from the Greek for "elderly vision".

protanopia
A visual defect in which the retina fails to respond to the color red; so named from blindness to the color red, which is regarded as the first of the primary colors.
psychanopsia
1. Mind blindness.
2. Visual agnosia, or the inability to recognize objects by sight.

The subject sees the object, but cannot identify it; because of a lesion in the area of the occipital cortex.

ptomatopsia
A previous term for autopsy.
quadrant hemianopia
Blindness of the symmetrical quadrant (one fourth) of the field of vison in each eye.
rhodopsin
A bright-red photosensitive pigment found in the rod-shaped cells of the retina of certain fish and most higher vertebrates.

It is broken down by the action of dim light into retinal (layer of neurons, or nerve cells, that line the back of the eye) and opsin (several compounds that form the protein component of the light-sensitive retina pigment).

scotopia
1. The adaptation of the eye to darkness.
2. Loss of color perception, with the ability to discern only shades of black and white.
3. Vision when the eye is adapted to the dark; also: night vision, rod vision, and twilight vision.
senile lenticular myopia, second sight
1. Improved near vision in the aged as a result of increased refractivity of the nucleus of the lens causing myopia.
2. The power of discerning what is not visible to the physical eye, or of foreseeing future events; such as are of a disastrous kind, the capacity of a seer or prophetic vision.

Related references to "eye" or "eye part" word families: blepharo-; core-; corneo-; eye, eyes; irido-; lenti-, lens-; lenticulo-; ocelli-; oculo-; ophthalmo-; phaco-; pupillo-; retino-; uveo-.

Cross references of word families that are related directly, or indirectly, to: "appear, visible, visual, manifest, show, see, reveal, look": blep-; delo-; demonstra-; -orama; pare-; phanero-; phant-; pheno-; scopo-; spec-; vela-, veal-; video-, visuo-.