This is the 7490th most frequent Japanese word.
光沢
Gloss or sheen.
The word 光沢 (koutaku) refers to the shiny or glossy surface aspect that adds aesthetic appeal to the painting.
その絵には光沢があり、非常に美しいです。
The painting has a luster and is extremely beautiful.
光沢 here suggests the shininess or polished appearance of the car's surface.
新しい車の塗装には光沢が見られます。
The new car's paint has a visible sheen.
In this case, 光沢 is used to describe the subtle shine or reflective quality that conveys elegance.