penumbra
/pəˈnʌm.bɹə/
Word Rarity
Very rare
Frequency: Zipf frequency 2.25 in modern English
14
Scrabble Score
8
Letters
3
Syllables
8
Unique Chars
Meaning
noun
A region around the edge of a sunspot, darker than the sun's surface but lighter than the middle of the sunspot.
noun
An area of uncertainty or intermediacy between two mutually exclusive states or categories.
noun
An area that lies on the edge of something; a fringe.
noun
Something related to, connected to, and implied by, the existence of something else that is necessary for the second thing to be full and complete in its essential aspects.
noun
A region of the brain that has lost only some of its blood supply, and retains structural integrity but has lost function.
Example Sentences
- "[A]ny penumbral fringe that may be detected cannot be well distinguished from the effects of the true penumbræ; […]"
- "The other places see the penumbra of the moon's shadow fall on the earth, so the eclipse is partial, and part of the sun's disc is still visible."
- "In the boiling temperature of 119 ° F – the hottest they had experienced so far – they watched as the penumbra of Venus blurred its outline at the precise moment the disc crossed the sun."
- "The part of the moon that remains in the penumbra receives some direct sunlight, and the glare is usually great enough to prevent your seeing the faint coppery glow of the part of the moon in the umbra."
- "The atmosphere was very clear, evidenced by the steadiness with which the mottling of the sun’s surface and the penumbræ of several spots were visible."
- "The velocities found in the penumbræ of spots generally increase with the distance from the centre of radiation, the motion being zero at some point in the umbra, and accelerating outwards."
Etymology
Origin
- Source language: Latin
Word Breakdown
- Root: pēnumbra, paene