The generation and emission of light by living organisms; such as, fireflies, some bacteria and fungi, and many marine animals.

Emission of light accompanying a chemical reaction, as in the oxidation of phosphorus.

The emission of light by something such as a gas or phosphor resulting from a high-frequency electric discharge.

The amount of light, evaluated according to its capacity to produce visual stimulation, that reaches a unit of surface area during a unit of time. It is measured in lux.

Giving off light.

1. To make something visible or bright with light, or be lit up.
2. To decorate something with lights for a celebration.
3. To make something clear, or easier to ulnderstand and to appreciate.
4. To add colored letters, illustrations, and designs to a manuscript or the borders of a page.
5. To provide someone with knowledge or with intellectual or spiritual enlightenment.

Any one of various groups of people in history claiming to have received special religious or spiritual enlgihtenment.

Informative and enlightening, often by revealing or emphasizing facts that were previously obscure.

1. The provision of light to make something visible or bright, or the fact of being lit up.
2. The amount or strength of light available in a place or for a purpose.
3. The process of clarifying or explaining something.
4. Intellectual or spiritual enlightenment.
5. A colored letter, design, or illustration decorating a manuscript or page, or the art or act of decorating written texts.
6. In medicine, throwing light on the body or a part or into a cavity for diagnostic purposes or lighting an object under a microscope.

A psychotic state of exaltation in which one has delusions and hallucinations of communion with supernatural or exalted beings.

1. In physics, the SI unit of luminous flux, equal to the amount of light crossing a unit area at a unit distance from a light source of luminous intensity of one candela. Symbol lm.
2. In anatomy, the space inside any tubular structure in the body, e.g., an intestine, artery, or vein.
3. In botany, the cavity within a plant cell wall.

1. The condition or quality of emitting or reflecting light.
2. A measure of the brightness of a surface equal to the amount of luminous flux arriving at, passing through, or leaving a unit area of surface. It is measured in candelas per square meter.

A small candle set inside a paper bag that has been weighted with sand, usually placed outdoors with others as a Christmas decoration; originally, the plural of luminatrium.

1. An eminent or famous person.
2. An object, especially a celestial body, that emits light.
3. Relating to or characterized by light.

1. To emit light by phosphorescence, fluorescence, or bioluminescence.
2. Emission of light from a body as a result of a chemical reaction.

1. The emission of light produced by means other than heat (incandescence), e.g., phosphorescence, fluorescence, or bioluminescence.
2. The light emitted by luminescence.

1. Generating or giving off light.
2. Producing or conveying light.

1. One who studies the luminescent phenomena in living organisms.
2. One versed in the study of illuminations of manuscripts.

1. A luminescent material that emits radiation by absorbing and then converting a portion of incident energy.
2. An atom or atomic grouping in an organic compound that increases its ability to emit light.

1. The state or quality of being luminous.
2. The energy radiated per second by a celestial body.
3. The visual perception of the extent to which an object emits light.
4. Something that emits light.

1. Full of light.
2. Emitting or reflecting light, with or without accompanying heat.
3. Immensely bright or brightly illuminated.
4. Evaluated on the basis of the visual sensation produced in an observer rather than energy measurements.

A plankton that produces light. When present in large groups, they make the sea appear to glow.

1. A reference to bioluminescent organisms emitting light during darkness.
2. A term used to describe high clouds that are visible at night.

Someone who collects matchboxes and matchbooks as a hobby.

1. The emission of light from a substance as a result of the absorption of electromagnetic radiation. The frequency of the light emitted is lower than that which is absorbed.
2. Luminescence caused by visible light or by infra-red or ultraviolet radiation.

Allowing the passage of radiant energy, such as X-rays, to a varying extent depending on the nature of the object. Also, roentgenolucent.

In physics, a luminescent phenomenon that is produced in certain materials by high-frequency sound waves or phonons.

Having or being a speed less than that of light.

Having or being a speed greater than that of light.

1. Luminescence resulting from exposure to high temperature.
2. The phenomenon in which radiant energy absorbed by certain materials, such as lithium fluoride, is later released in the form of light when these materials are heated.

To shine a bright light through a body organ or cavity to detect diseases or other abnormalities. when pus or a lesion is present, the transmission of light is diminished or absent.

This test is most commonly performed on newborns or infants with hydrocephalus , or males suspected of having a hydrocele (accumulation of serus fluid in a saclike cavity). The test may also be performed on breast tissue to detect lesions and cysts . In newborns, a bright halogen light may be used to transilluminate the chest cavity if it is suspected they have a pneumothorax . Transillumination through the chest is only possible on small newborns.

Areas filled with air or fluid that is not native to that location have increased light transmission and transilluminate when they should not. For example, in a darkened room, a newborn infant's head can be seen to light up brightly when transilluminated if there is excess fluid present (suggesting hydrocephalus).

One of a range of new digital technologies that is helping to improve diagnostic techniques is the Difoti (digital imaging fiber optic transillumination). One application of the Difoti is with dentists when a wand is positioned above each tooth and as light passes through the enamel, any cavities or other irregularities alter the light pattern during transillumination and the information is captured by the wand’s sensor and transmitted to a display

Luminescence caused by friction; the glow or emission of light that results from friction or mechanical pressure.

Thermoluminescence (luminescence resulting from exposure to high temperature) produced in a material as a result of friction.

1. Not illuminated or without light.
2. Not spiritually or mentally enlightened.