addition

This word carries a sense of expansion and accumulation. It suggests a positive or neutral growth where the original entity remains intact but is enhanced or enlarged by the new element. It is frequently used in professional, architectural, and mathematical contexts to describe a deliberate increase. In social or domestic settings, the term softens the introduction of a new member, framing them as a complementary piece that completes or improves the existing group. This differs from words like supplement or appendage, which can sometimes imply that the added part is secondary or unnatural.