I walk the line...

September 6, 2006 2:30 PM

Is there a word (in any language) that describes the precise separation between shadow and light?

I love the shadows of late afternoon. Specifically, I love to walk straddling that line; shadow covering half of my face, and the sun blinding the other half. When I see the line in front of me, I always wonder if anyone has named it (and this time, I finally remembered to ask here!)

posted by zerokey to science & nature (23 comments total)

Terminator?
posted by A189Nut at 2:30 PM on September 6, 2006

penumbra?
posted by luriete at 2:32 PM on September 6, 2006

Terminator_(Solar)
posted by blue_beetle at 2:39 PM on September 6, 2006

Chiaroscuro
posted by b33j at 2:46 PM on September 6, 2006

I guess I'll have to accept terminator.

I was hoping there was something more poetic :)
posted by zerokey at 2:47 PM on September 6, 2006

ooh..posted too soon..thanks b33j!
posted by zerokey at 2:48 PM on September 6, 2006

Chiaroscuro is indeed a lovely word, but it doesn't really describe what you're looking for -- i.e., the actual line where light and dark meet. It describes the interplay of light and dark, often in high contrast to each other.
posted by scody at 2:51 PM on September 6, 2006 [1 favorite]

It'd probably be either the periphery or the penumbra, depending upon how distinct the distinction between the two areas is.
posted by Pseudoephedrine at 2:57 PM on September 6, 2006

Definitely terminator. Remember the ending of The Terminator when Sarah Connor drives toward the mountain landscape that was half in shadow, half in light?
posted by infinitewindow at 3:08 PM on September 6, 2006

Satai, in a loose, geeky sci-fi poetry sort of way.
posted by cortex at 3:13 PM on September 6, 2006

Not specifically for this but can apply to it: barzakh, an Arabic word for 'boundary.' There's a nice explanation here:

A limit or boundary separating two things is called barzakh in Arabic, which explains why the intermediate realm that separates the temporary and evanescent life of this world from the eternal life of the hereafter is also called barzakh.

posted by languagehat at 3:52 PM on September 6, 2006 [1 favorite]

step?
posted by popcassady at 3:57 PM on September 6, 2006

Yeah, the terminator line. Umbra and Prenumbra are shadow or mostly-shadow, respectively.
posted by absalom at 4:01 PM on September 6, 2006

People who are into faerie witchcraft use "the between" to refer to that dividing line, doorways, and other such "between" places. They say that faeries like it in the between.
posted by leapingsheep at 4:14 PM on September 6, 2006

How about: The Limn?
posted by vacapinta at 4:26 PM on September 6, 2006

I was going to suggest 'barzakh', too, because it is used in the sense of this metaphysical or non-determinate boundary, like the inconceivable boundary between two continuous solids.
posted by sonofsamiam at 4:28 PM on September 6, 2006

I'd vote for "limn," but it's usually a verb -- as in to traverse the line you're describing. Part of the problem may be that it's not actually a line -- it's the abutment of two adjacent things that we consider nouns -- "light" and "dark" -- but that are actually more like colors or states of being. (e.g., there is no "line" between red and white on the US flag, or between feeling happy or sad). Chiaroscuro and gloaming are great words, but they're not what you're looking for, as they imply a mix of light and dark (as in dusk).

I'm sure Baudrillard or Lyotard had something to say about this...
posted by turducken at 4:49 PM on September 6, 2006

Daniel Boorstin describes that line as a "verge" in The Exploring Spirit.

For a verge, in my vocabulary of world history, is a boundary between anything and anything else--including, of course, the boundary between the known and the unknown, the familiar and the strange.

Light is the known, dark is the unknown. Who know that world history was poetic?
posted by Jeff Howard at 5:00 PM on September 6, 2006

Joseph Conrad wrote a book called The Shadow Line, and the title refers to both the dark edge of a storm moving across the water and all sorts of metaphors and arty stuff on top of that.
posted by cardboard at 5:48 PM on September 6, 2006

The word "cusp" springs to mind, it describes the concept in a general sense. Unfortunately, not specific to light and shade.
posted by knave at 7:46 PM on September 6, 2006

In drawing, this transition point is sometimes called the "crest shadow" and is crucial in bringing out the form of what is being depicted.
posted by extrabox at 9:02 PM on September 6, 2006

This question reminded me of Kim Stanley Robinson's enjoyable short story "Mercurial," a murder mystery set on the first rock from the Sun. It takes place in a domed city on rails that follows Mercury's sun-shade boundary. The city's name: Terminator.

Although terminator is indeed the (astronomical) term you asked about, another less Teutonic possibility is demarcator. And Star Trek fans might know it as a gorshin.
posted by rob511 at 11:38 PM on September 6, 2006 [1 favorite]

Something similar to "event horizon" ?
posted by vanoakenfold at 1:55 AM on September 7, 2006