Dictionary
um•bra
Pronunciation: (um'bru), [key]—
n.,
—pl. -bras, -braePronunciation: (-brē). [key]
1. shade; shadow.
2. the invariable or characteristic 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. Cf.
penumbra (def. 1a).
b. the dark central portion of a sunspot. Cf.
penumbra (def. 1b).
4. a phantom or shadowy apparition, as of someone or something not physically present; ghost; spectral image.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.