Twinkle: it’s as much about dark as light.
A visible twinkle always has a counterpart–a yin to its yang, eyes closed and opened.
Unlike a sparkle, a shimmer, or a beacon, a twinkle is an on-and-off illumination. Its hallmark is that, intermittently, no light is emitted from whatever source gives it life.
It has something to do with depth: a shimmer quivers at the surface, but a twinkle in the eye comes from animation within.
Unlike a gleam and akin to a sparkle, a twinkle can come from an impy, sometimes conspiratorial impulse. A twinkle does not take itself too seriously.
It also has to do with duration. A lighthouse beam flashes on and off, but its sustained notes endure beyond the life of a twinkle.
A steady light source can segue into a mere twinkle: the wind may lift branches or vines across its surface, giving the illusion of waxing and waning light; an electrical pulse may weaken and flicker.
Cities and towns will twinkle as some parents finish bedtime stories and click off lamps, while others return to dark homes and reset their points of light on the landscape.
A twinkle is often anchored in light seen from a distance, as it was in “Ulysses“:
It may be Scrooge-like to observe that the erstwhile twinkle seems slightly overused in Clement Clarke Moore’s “A Visit from St. Nicholas,” where it appeared twice in just a handful of lines: