(physics) A path a photon or a group of photons takes through space, visible as a column of light. / (idiomatic) An inspiring or enlightening person or thing.

plural of ray of light

(idiomatic, often in the negative or ironic) That which is good, pleasant, pure, etc.

(astronomy, physics) A unit of length equal to the distance light travels in one second: approximately 300,000 kilometers

plural of light cone

The time when light first appears in the morning; dawn, especially the start of dawn. / (astronomy) The first use of a telescope or other instrument to capture an astronomical image.

A light exhibiting very rapid regular alternations of light and darkness, normally sixty flashes per minute.

(nautical) A rhythmic light (in a lighthouse) in which all durations of light and darkness are equal.

A light in which the total duration of light in each period is clearly longer than the total duration of darkness and in which the intervals of darkness (occultations) are all of equal duration.

A small, persistent flame used to ignite gas. / A small telltale lamp on a dynamo or battery circuit whose brightness indicates the voltage of the current.