A breast reduction (reduction mammoplasty) is the surgical removal of breast tissue, fat, and skin. It decreases breast size but does not entirely remove them.
A weak chin is neither a medical condition nor a result of one. Rather, it is a term some people use to describe when the chin is less prominent on the face. A weak chin is not a healthcare issue. Rather, it is a cosmetic concern that some people have regarding the shape and predominance of their chin.