Noun
waxing moon (plural waxing moons)
A moon (usually the Moon, that is, Earth's moon) when it appears larger each night as it progresses from a new moon to a full moon: a moon in any of the increasing lunar phases.
If you want your hair to be thicker, cut it when the moon is about to be full - a heavy, full, waxing moon. Do not cut it when the moon's waning. Matthew McConaughey