n. (pl. umbras or umbrae) Astron. 1 a total shadow usu. cast on the earth by the moon during a solar eclipse. 2 the dark central part of a sunspot (cf. PENUMBRA). umbral adj.
[ L, = shade ]
UMBRA
Meaning of UMBRA in English
Concise Oxford English dictionary. Краткий оксфордский словарь английского языка. 2012