- the phase of the moon when it is on the side of the earth away from the sun, with its entire face reflecting sunlight to the earth
- the time of month when such a moon is seen
- The phase of the moon at which the moon, as viewed from Earth, appears to be fully illuminated by the sun. The full phase marks the half-way point of a single revolution of the moon around the earth.
- The period of the month when such a moon occurs.
(plural full moons)