gegenschein
A faint brightening of the night sky in the region of the ecliptic directly opposite the Sun.
countable, uncountable
My object in appearing before the Association, at this time, is to present the observations of several other persons on the gegenschein or completed arch of the zodiacal light, of which I have received accounts since our meeting in Motreal.
Where it comes from
Borrowed from German Gegenschein (“counter-shine”), from gegen- + Schein.
Adapted from the Wiktionary entry gegenschein (CC BY-SA 4.0).