noun.
Light reflected by the earth: same as earth-shine.
the GNU version of the Collaborative International Dictionary of English
noun.
The sunlight reflected from the earth to the moon, by which we see faintly, when the moon is near the sun (either before or after new moon), that part of the moon's disk unillumined by direct sunlight, or “the old moon in the arms of the new.”
"I remember hearing about research that suggested that the amount of earth's reflected radiation or "earthlight" found by measuring the light intensity on the dark side of the moon has increased."