umbra

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umbra

um·bra

 (ŭm′brə)
n. pl. um·bras or um·brae (-brē)
1. A dark area, especially the blackest part of a shadow from which all light is cut off.
2. Astronomy
a. The completely dark central portion of the shadow cast by the earth, moon, or other body during an eclipse.
b. The darkest region of a sunspot.

[Latin, shadow.]

um′bral adj.

umbra

(ˈʌmbrə)
n, pl -brae (-briː) or -bras
1. (Astronomy) a region of complete shadow resulting from the total obstruction of light by an opaque object, esp the shadow cast by the moon onto the earth during a solar eclipse
2. (Astronomy) the darker inner region of a sunspot
[C16: from Latin: shade, shadow]
ˈumbral adj

um•bra

(ˈʌm brə)

n., pl. -bras, -brae (-brē).
1. shade; shadow.
2. the usual accompaniment or companion of a person or thing.
3. Astron.
a. the complete or perfect shadow of an opaque body, as a planet, where the direct light from the source of illumination is completely cut off.
b. the dark central portion of a sunspot.
4. a phantom or ghost.
[1590–1600; < Latin: shade, shadow]
um′bral, adj.

um·bra

(ŭm′brə)
1. The darkest part of a shadow, especially the completely dark portion of the shadow cast by Earth, the moon, or another body during an eclipse.
2. The darkest region of a sunspot. Compare penumbra.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.umbra - a region of complete shadow resulting from total obstruction of lightumbra - a region of complete shadow resulting from total obstruction of light
shadow - shade within clear boundaries

umbra

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

umbra

n pl <-s or -e> (Astron: = shadow) → Kernschatten m; (in sunspot) → Umbra f
References in periodicals archive ?
Using the latest in field-effect technology, the Antumbra User Interface from Philips wakes up when it detects a person's magnetic field near it and illuminates the device to the proper light levels based on a built-in ambient light sensor.
That is, the center of the Moon's shadow - known as the antumbra during an annular eclipse - will juuuust miss the Earth and instead pass scant kilometers above the Antarctic continent," read the explanation on the Web site.
Just 10 minutes into the annular track, the antumbra encounters the southern islands of Japan.