penumbra

penumbra Definition

penum·bra (pi num′brə)

noun pl. -·brae′-brē′ or -·bras

the partly lighted area surrounding the complete shadow (umbra) of a body, as the moon, during an eclipse
the less dark region surrounding the dark central area of a sunspot
a vague, indefinite, or borderline area

Etymology: ModL < paene, almost (see passion) + umbra, shade

penumbra Related Forms

penum′·bral adjective

penumbra Usage Examples

Adjective modifier

ischaemic: Group differences in average volume of ischaemic penumbra salvaged will be analyzed by t-test, adjusting for baseline differences in prognostic variables.

Converse of object

call: All but the smallest spots show a dark central portion called the umbra with a lighter outer area called the penumbra.
follow: Well, consider the following penumbra of events that surround the current rumpus.

Converse of subject

surround: It is surrounded by the penumbra that receives some light from the light source.

Modifies a noun

effect: The penumbra effect may be compounded by the presence of variable blood flow through cutaneous pulsatile venules.

penumbra Quotes

A penumbra of somber dignity has descended over his reputation.

—Atlas,James

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