The word wax means to grow larger," while wane means "to grow

smaller." If the lighted portion of a waxing crescent is the same size as

that of a waning crescent, why do you think these terms are used?

Answer: waxing~ Wax as an intransitive verb means to grow in size, where

as wane means to shrink in size. In terms of moon phases, waxing means getting fuller, going towards a full moon. Waning - Waning is the opposite, getting thinner, going towards a new moon.