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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.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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Adj.1.penumbral - of or pertaining to the region of partial shadow around an umbra
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
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He sees penumbral visions of himself titubating fantastically through days and nights of space and stars.
Penumbral eclipse began at 23:44 PST (on 16th July, 2019), while partial eclipse started at 01:02 PST on 17th July, 2019, PMD source said.
PAGASA said the penumbral eclipse begins at 2:42 a.m.
A penumbral lunar eclipse occurs when the moon does not fall in the umbra at all and is always present in the penumbra.
The penumbral coverage, on the other hand, is expected to go on for 5 hours, 33 minutes, 43 seconds.
Penumbral eclipse will begin at 23:44 PST (on 16th July, 2019), while partial eclipse will begin at 01:02 PST on 17th July, 2019, the met office said, private news channel reported.
The first lunar eclipse of the year will occur at dawn tomorrow, Qatar Calendar House (QCH) has said, and people in Qatar will have the opportunity to witness the penumbral phase only.
There are three types of lunar eclipses -- total, partial and penumbral. A total eclipse is when the moon is completely in Earth's umbral shadow.
However, residents of the Middle East region (including Qatar) will be able to watch only the penumbral phase of the lunar eclipse, he added.
For instance, which solution to the sorites paradox we endorse, as well as our treatment of penumbral connections, standards of comparison, forced march sorites, the interaction between context shifts and vague expressions, among others, depend on this.
Penumbral eclipse begins : This starts when the outer (and lighter) part of the Earth's shadow begins moving across the Moon