Definition - What does Cincher mean?
A cincher is a garment that is worn around the waist. It can be tightened with ties or hooks to emphasize the 'hourglass' body shape. Similar to a corset, a cincher can be worn under garments or implemented as a fetish object.
Kinkly explains Cincher
There is a significant difference between a utilitarian cincher used primarily to control midsection bulge, and a corset-style cincher, which can be used to 'train' waist size to significantly smaller dimensions. The former is typically made with stretchy material, such a rubber, while the latter may be made with boning, and decorative fabrics (like satin).