The fully shaded inner region of a shadow cast by an opaque object, especially the area on the earth or moon experiencing the total phase of an eclipse.

During the solar eclipse, the umbra of the moon's shadow moved across the Earth's surface.

A region of complete shadow resulting from total obstruction of light.

The umbra of the tree provided a cool spot to sit on a hot summer day.

The central, darkest part of a sunspot.

Astronomers observed the sunspot's umbra to study solar activity.