A "hairpiece" generally refers to a detachable accessory that someone wears on their head to simulate natural hair. There are a variety of synonyms for this item, including "wig," "hair extension," or "topper." A "wig" typically refers to a full head covering that is designed to mimic natural hair growth. "Hair extensions" can be clipped onto existing hair to add length or volume, while a "topper" is a smaller piece that is specifically designed to add coverage to thinning sections of the scalp. Other synonyms for "hairpiece" that might be used include "hair system," "hair unit," or "hair replacement," depending on the specific type of product being referred to.