penumbra

[ pi-nuhm-bruh ]

/ pɪˈnʌm brə /

SEE SYNONYMS FOR penumbra ON THESAURUS.COM

noun, plural pe·num·brae [pi-nuhm-bree], /pɪˈnʌm bri/, pe·num·bras.

Astronomy.

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.Compare umbra (def. 3a).
the grayish marginal portion of a sunspot.Compare umbra (def. 3b).

a shadowy, indefinite, or marginal area.

Origin of penumbra

First recorded in 1660–65; from New Latin penumbra (coined by Johann Kepler in 1604), equivalent to Latin paen- prefix meaning “almost” + umbra “shade”; see pen-, umbra

OTHER WORDS FROM penumbra

pe·num·bral, pe·num·brous, adjective

Words nearby penumbra

pentyl group, penuche, penuchle, penult, penultimate, penumbra, penurious, penury, Penutian, Penza, Penzance

Dictionary.com UnabridgedBased on the Random House Unabridged Dictionary, © Random House, Inc. 2020

Example sentences from the Web for penumbra

In person, Waltz is equally charming, but without the penumbra of menace that comes with having Nazi goons just outside the door.
Tarantino's Glorious Nazi|Paul Cullum|August 16, 2009|DAILY BEAST
I want to whisper low-toned, intimate talk, in keeping with this penumbra of the dusk.
Glimpses of Bengal|Sir Rabindranath Tagore
This is the entrance into the “penumbra” (or “Partial shade”).
The Story of Eclipses|George Chambers
They are generally surrounded by an aureola known as the penumbra, and sensibly less luminous than the other portions of the orb.
Chambers's Edinburgh Journal, No. 441|Various

Each spot is quite sharply divided into an umbra and a penumbra.
Astronomy for Young Folks|Isabel Martin Lewis
Now I will try and explain to you what the Penumbra is and how it is produced.
The Life of Roger Langdon|Roger Langdon

British Dictionary definitions for penumbra

penumbra

/ (pɪˈnʌmbrə) /

noun plural -brae (-briː) or -bras

a fringe region of half shadow resulting from the partial obstruction of light by an opaque object

astronomy the lighter and outer region of a sunspot

painting the point or area in which light and shade blend

Compare umbra

Derived forms of penumbra

penumbral or penumbrous, adjective

Word Origin for penumbra

C17: via New Latin from Latin paene almost + umbra shadow

Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Scientific definitions for penumbra

penumbra

[ pĭ-nŭm′brə ]

Plural penumbras penumbrae (pĭ-nŭm′brē)

A partial shadow between regions of full shadow (the umbra) and full illumination, especially as cast by Earth, the Moon, or another body during an eclipse. During a partial lunar eclipse, a portion of the Moon's disk remains within the penumbra of Earth's shadow while the rest is darkened by the umbra. See Note at eclipse.

The grayish outer part of a sunspot. Compare umbra.

单词	penumbra
释义	penumbra [ pi-nuhm-bruh ] / pɪˈnʌm brə / SEE SYNONYMS FOR penumbra ON THESAURUS.COM noun, plural pe·num·brae [pi-nuhm-bree], /pɪˈnʌm bri/, pe·num·bras. Astronomy. 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.Compare umbra (def. 3a). the grayish marginal portion of a sunspot.Compare umbra (def. 3b). a shadowy, indefinite, or marginal area. Origin of penumbra First recorded in 1660–65; from New Latin penumbra (coined by Johann Kepler in 1604), equivalent to Latin paen- prefix meaning “almost” + umbra “shade”; see pen-, umbra OTHER WORDS FROM penumbra pe·num·bral, pe·num·brous, adjective Words nearby penumbra pentyl group, penuche, penuchle, penult, penultimate, penumbra, penurious, penury, Penutian, Penza, Penzance Dictionary.com UnabridgedBased on the Random House Unabridged Dictionary, © Random House, Inc. 2020 Example sentences from the Web for penumbra In person, Waltz is equally charming, but without the penumbra of menace that comes with having Nazi goons just outside the door. Tarantino's Glorious Nazi\|Paul Cullum\|August 16, 2009\|DAILY BEAST I want to whisper low-toned, intimate talk, in keeping with this penumbra of the dusk. Glimpses of Bengal\|Sir Rabindranath Tagore This is the entrance into the “penumbra” (or “Partial shade”). The Story of Eclipses\|George Chambers They are generally surrounded by an aureola known as the penumbra, and sensibly less luminous than the other portions of the orb. Chambers's Edinburgh Journal, No. 441\|Various Each spot is quite sharply divided into an umbra and a penumbra. Astronomy for Young Folks\|Isabel Martin Lewis Now I will try and explain to you what the Penumbra is and how it is produced. The Life of Roger Langdon\|Roger Langdon British Dictionary definitions for penumbra penumbra / (pɪˈnʌmbrə) / noun plural -brae (-briː) or -bras a fringe region of half shadow resulting from the partial obstruction of light by an opaque object astronomy the lighter and outer region of a sunspot painting the point or area in which light and shade blend Compare umbra Derived forms of penumbra penumbral or penumbrous, adjective Word Origin for penumbra C17: via New Latin from Latin paene almost + umbra shadow Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012 Words related to penumbra shadow, dark, gloom, obscurity, shade, darkness, dusk, screen, cover, shadiness, umbrage, blackness, coolness, umbra, semidarkness, gloominess, adumbration, shelter, protection, dimness Scientific definitions for penumbra penumbra [ pĭ-nŭm′brə ] Plural penumbras penumbrae (pĭ-nŭm′brē) A partial shadow between regions of full shadow (the umbra) and full illumination, especially as cast by Earth, the Moon, or another body during an eclipse. During a partial lunar eclipse, a portion of the Moon's disk remains within the penumbra of Earth's shadow while the rest is darkened by the umbra. See Note at eclipse. The grayish outer part of a sunspot. Compare umbra. The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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penumbra

noun, plural pe·num·brae [pi-nuhm-bree], /pɪˈnʌm bri/, pe·num·bras.

Origin of penumbra

OTHER WORDS FROM penumbra

Words nearby penumbra

Example sentences from the Web for penumbra

British Dictionary definitions for penumbra

noun plural -brae (-briː) or -bras

Derived forms of penumbra

Word Origin for penumbra

Words related to penumbra

Scientific definitions for penumbra

Plural penumbras penumbrae (pĭ-nŭm′brē)