Definition of "Scintillation" :

noun: the twinkling of the stars caused when changes in the density of the earth's atmosphere produce uneven refraction of starlight

noun: the quality of shining with a bright reflected light

noun: a brilliant display of wit

noun: a rapid change in brightness; a brief spark or flash

noun: (physics) a flash of light that is produced in a phosphor when it absorbs a photon or ionizing particle