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.