/
ˈʌmbrə/
n.
 (pl. umbras or umbrae  
/-briː/
)
  - the fully shaded inner region of a shadow cast by an opaque object, especially the area on the earth or moon experiencing totality in an eclipse.
 - Astronomy  the dark central part of a sunspot.
 
Derivative
Etymology
C16 (denoting a ghost): from L., lit. ‘shade’.