penumbra

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penumbra

pe·num·bra

 (pĭ-nŭm′brə)
n. pl. pe·num·bras or pe·num·brae (-brē)
1. A partial shadow, as in an eclipse, between regions of complete shadow and complete illumination.
2. The diffuse outer part of a sunspot.
3. An area in which something exists to a lesser or uncertain degree: "The First Amendment has a penumbra where privacy is protected from governmental intrusion" (Joseph A. Califano, Jr.).
4. An outlying surrounding region; a periphery: "Downtown Chicago and its penumbra also stand rejuvenated" (John McCormick).

[New Latin pēnumbra : Latin paene, almost + Latin umbra, shadow.]

pe·num′bral, pe·num′brous adj.

penumbra

(pɪˈnʌmbrə)
n, pl -brae (-briː) or -bras
1. (Astronomy) a fringe region of half shadow resulting from the partial obstruction of light by an opaque object
2. (Astronomy) astronomy the lighter and outer region of a sunspot
3. (Art Terms) painting the point or area in which light and shade blend
[C17: via New Latin from Latin paene almost + umbra shadow]
peˈnumbral, peˈnumbrous adj

pe•num•bra

(pɪˈnʌm brə)

n., pl. -brae (-brē), -bras.
1.
a. the partial or imperfect shadow outside the complete shadow of an opaque body, as a planet, where the light from the source of illumination is only partly cut off.
b. the grayish marginal portion of a sunspot.
2. a shadowy, indefinite, or marginal area.
[1660–70; < New Latin, = Latin paen(e) almost + umbra shade]
pe•num′bral, pe•num′brous, adj.

pe·num·bra

(pĭ-nŭm′brə)
1. A partial shadow between regions of complete shadow and complete illumination, especially as cast by Earth, or the moon, over another body during an eclipse.
2. The grayish outer part of a sunspot. Compare umbra.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.penumbra - a fringe region of partial shadow around an umbrapenumbra - a fringe region of partial shadow around an umbra
shadow - shade within clear boundaries

penumbra

noun
Comparative darkness that results from the blocking of light rays:
Translations

penumbra

[pɪˈnʌmbrə] N (penumbras or penumbrae (pl)) [pɪˈnʌmbriː]penumbra f

penumbra

n pl <-s or -e> → Halbschatten m
References in periodicals archive ?
But when Hujar steps back, as he does in a number of sweeping shots of institutional architecture--corporate high-rises, City Hall, an avenue of nine-teenth-century office buildings--the light seems almost beneficent, emanating in phosphorescent penumbrae from intermittently illuminated windows.
The fact that the Worcester monk could apparently distinguish the umbrae and penumbrae of the sunspots shows his amazing eye for detail.