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  • noun

Synonyms for umbra

comparative darkness that results from the blocking of light rays

Words related to umbra

a region of complete shadow resulting from total obstruction of light

Related Words

References in periodicals archive ?
On the facing page, the bottom diagram shows the Moon's passage through the umbra and penumbra (pale outer fringe) of Earth's shadow.
More dramatic and interesting are views of the sharp demarcation curve between the umbra and penumbra.
But that's a mistake if you really want to capture the sharp line of demarcation between umbra and penumbra.
But we prefer to avoid the terms umbra and penumbra and adopt an atmospheric model instead, where the Earth is likened to a ball of gas.