Word of the Week: Crepuscular

So, avuncular (unclelike), saturnine (sluggish), sybaritic (pleasure-loving), antediluvian (primitive), concomitant (accompanying), uxorious (fawning), lucubrate (laborious studying), vulpine (foxlike), fissiparous (fractious), skeuomorph (look it up yourself), obdurate (stubborn), syllepsis (zeugma), parlous (perilous) and how about… crepuscular?

They say a picture is worth a thousand words. And yet here is a picture that is worth only one.

It comes from the Latin crepusculum, which means “twilight.” Webster’s fourth defines crepuscular, an adjective, first as “of or like twilight; dim,” and then as “active at twilight or just before sunrise.”

So two useful areas of literary composition represented. Twilightlike qualities evoke poetry, an end to toil and perhaps light brooding; activity at twilight brings to mind insects or, if you will allow me, graverobbers. Spanning the two, you could dream of crepuscular miscreants scuttling in crepuscular crevices, clawlike clavicles crinkling with craniums, capitates and coccyges. If you were so inclined.

That’s not all. With this word we also have a scientific component, as demonstrated in the picture above (which comes from the I’m-sure-you-check-it-every-day Earth Science Picture of the Day Web site). Those shafts of seeming divine whatever are known as crepuscular rays. It happens any time sunlight is partly blocked by clouds or other objects; scientists didn’t muddle around thinking of other words to name the phenomenon because that sort of thing is most obvious in the crepuscular hours.

Crepuscular rays, as seen from the International Space Station (Oct. 18, 2011).

Now. The interesting thing is these shafts of light, to an observer on the ground, usually appear to radiate from a single point, especially when they are seen from the side. In fact, these rays are parallel (see photo at right) to each other, because the sun is so large and so far away; the single-point thing is an illusion.

As the skeptic, astronomer and budding TV star Phil Plait wrote on his blog last year, it is the same idea that “makes railroad tracks or long roads appear to converge in the distance.”

As in,

These animals are crepuscular by nature, which means they’re most active during dusk and dawn.

via Deer out in full force in fall on rural roads | Other Sports | Sports | Ottawa Sun.

British upstart and Donmar vet Jamie Lloyd’s new production shows signs of rising sap, and features a great many moments of surprising verve, and a few deathly stretches of crepuscular indulgence.

via Theater Review: Cyrano — Vulture.

Everywhere the rich repertory of Moorish decoration is celebrated, using a surprising palette that at times echoes the freshness and gaiety of the surrounding garden; at other times—as in the ravishing library—applies more sombre, mysterious, crepuscular tones.

via A Magician from Memphis – WSJ.com.