Word Study
earthlight
CIDE DICTIONARY
earthlight, n.
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.” [Webster 1913 Suppl.]
For further exploring for "earthlight" in Webster Dictionary Online