scintillation

noun

1. the act of scintillating; sparkling.
2. a spark or flash.
3. Astronomy. the twinkling or tremulous effect of the light of the stars.
4. Meteorology. any small-scale twinkling or shimmering of objects that are viewed through the atmosphere, caused by an interception of the observer’s line of view by inhomogeneities in the atmospheric refractive index.
5. Physics.
   1. a flash of light from the ionization of a phosphor struck by an energetic photon or particle.
   2. random fluctuation of the amplitude, phase, or polarization of an electromagnetic wave.
6. (on a radar display) a slight, rapid shifting of a spot of light or the image of an object about its mean position.

noun

1. the act of scintillating
2. a spark or flash
3. the twinkling of stars or radio sources, caused by rapid changes in the density of the earth’s atmosphere, the interplanetary medium, or the interstellar medium, producing uneven refraction of starlight
4. physics a flash of light produced when a material scintillates

n.1620s, from Latin scintilationem (nominative scintillatio), noun of action from past participle stem of scintillare (see scintillate). n.

1. A spark; a flash.
2. A flash of light produced in a phosphor by absorption of an ionizing particle or photon.