—v.i. 1. to emit sparks.
2. to sparkle; flash: a mind that scintillates with brilliance. 3. to twinkle, as the stars.
4. Electronics.(of a spot of light or image on a radar display) to shift rapidly around a mean position.
5. Physics. a. (of the amplitude, phase, or polarization of an electromagnetic wave) to fluctuate in a random manner.
b. (of an energetic photon or particle) to produce a flash of light in a phosphor by striking it.