noun um·bra \ˈəm-brə\
plural umbras or um·brae \-(ˌ)brē, -ˌbrī\

Definition of UMBRA

:  a shaded area
a :  a conical shadow excluding all light from a given source; specifically :  the conical part of the shadow of a celestial body excluding all light from the primary source
b :  the central dark part of a sunspot
um·bral \-brəl\ adjective

Examples of UMBRA

  1. <strange noises were coming from the wooded umbra beyond our campfire>
  2. <during a solar eclipse observers located within the umbra experience a complete blocking of the sun by the moon>

Origin of UMBRA

First Known Use: 1638

Other Astronomy Terms

gibbous, nadir, nebulous, penumbra, retrograde, sidereal, syzygy, wane, wax, zenith


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