Harvest Moon
WordNet
noun
(1) The full moon nearest the September equinox
WiktionaryText
Etymology
Extra light provides longer hours for the harvesting that occurs in the Northern Hemisphere at this time of year.
Noun
- The first full moon of autumn by a tropical year.
- The full moon nearest the autumn equinox, when the moon rises the latest and lowest in the sky and seems to appear the biggest, as seen from the Northern Hemisphere.