The phrase "thin pillars" refers to pillars that are very slim or not very wide. Generally, it describes something that is small or slender in shape. Full definition
I like to sit high and see a lot of glass around me, with thinner pillars. (cheersandgears.com)
Up front, the low dash and thin pillars create an airy feeling. (automobilemag.com)
For improved aerodynamics and visibility, the all - new Chrysler luxury flagship's windshield has been raked back 3 inches, while rolled - framed doors with thinner pillars improve outward visibility by 15 percent. (thetorquereport.com)