Definition of "umbra"
noun:
-
A shadow.
from Wiktionary, Creative Commons Attribution/Share-Alike License -
The central region of a sunspot.
from Wiktionary, Creative Commons Attribution/Share-Alike License
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A shadow.
from Wiktionary, Creative Commons Attribution/Share-Alike LicenseThe central region of a sunspot.
from Wiktionary, Creative Commons Attribution/Share-Alike License