Final answer:
Waxing is the phase where the Moon's illuminated portion visible from Earth is gradually increasing, leading up to a full moon.
Step-by-step explanation:
The term waxing in the context of lunar phases refers to the period when the illuminated area of the Moon visible from Earth is increasing. This increase in brightness continues until the Moon achieves its full phase. When we talk about waxing, this directly corresponds to the Moon becoming more visibly illuminated as it progresses from a new moon towards a full moon, through its crescent and quarter phases, and eventually presenting as a waxing gibbous moon before it becomes full.
For example, after the new moon phase, the Moon appears as a thin crescent in the sky. Each night, the crescent gets thicker, leading up to the first quarter phase, where half of the Moon's visible hemisphere is illuminated. Subsequently, the Moon continues to wax until it forms a gibbous shape and ultimately becomes fully illuminated as a full moon, opposite the position of the Sun in the sky.