The phrase "slimmer appearance" means that someone or something appears to be thinner or more slender than they actually are.
Sentences with «slimmer appearance»
This will cover the extra fat and offer a more slim appearance. (sareelooks.com)
As we can see from the images, the handset has a smooth and slim appearance design, and metallic frame not only provides enhanced durability, but also adds more modern aesthetics. (gadgetsin.com)
Try also to wear a stripped top under the jackets they also give a more slim appearance to your waist area. (justtrendygirls.com)