not capable of being distinguished or differentiated; "the two specimens are actually different from each other but the differences are almost indistinguishable"; "the twins were indistinguishable"; "a colorless person quite indistinguishable from the colorless mass of humanity"
the flash of light that accompanies an electric discharge in the atmosphere (or something resembling such a flash); can scintillate for a second or more
abrupt electric discharge from cloud to cloud or from cloud to earth accompanied by the emission of light
increased pressure in the eyeball due to obstruction of the outflow of aqueous humor; damages the optic disc and impairs vision (sometimes progressing to blindness)
not to be placated or appeased or moved by entreaty; "grim determination"; "grim necessity"; "Russia's final hour, it seemed, approached with inexorable certainty"; "relentless persecution"; "the stern demands of parenthood"
of an obscure nature; "the new insurance policy is written without cryptic or mysterious terms"; "a deep dark secret"; "the inscrutable workings of Providence"; "in its mysterious past it encompasses all the dim origins of life"- Rachel Carson; "rituals totally mystifying to visitors from other lands"