penumbra

(redirected from penumbras)
Also found in: Thesaurus, Medical, Legal, Encyclopedia.
click for a larger image
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 classic literature ?
Slowly the penumbra, the shadow of a shadow, crept on over the bright surface, and as it crept I heard deep gasps of fear rising from the multitude around.
The penumbra, dense and dark, was the virtual screen of a figure which stood in it as still as some image erect in a niche or as some black-vizored sentinel guarding a treasure.
Recognizing false ischemic penumbras in CT brain perfusion studies.
Regions of interest were selected in ischemic penumbras and contralateral normal brain regions.
This table was later expanded to include the penumbras only after the photos were taken because it was not initially expected that the penumbra would be as visible, as it turned out on the photos.
The nuclei formed the body of the sun, which was relatively darker, and visible through the openings in both of these atmospheres; the penumbras were caused, according to Herschel, by the larger rupture in the second luminous layer.
La extrana (Toni Collette), la hermana (Rose Byrne), la esposa (Mary Beth Hurt), la madre (Marcia Gay Harden), la chica muerta (Brittany Murphy): estos son los personajes, o mejor, los arquetipos femeninos que Moncrieff, ex actriz televisiva, privilegia para urdir una inquietante historia de abismos y penumbras que roza lo lyncheano.
Douglas's opinion for the Court, locating the right of privacy in the penumbras and emanations of the specific guarantees of the Bill of Rights; it hooked the class.