What do dim and dim mean respectively?

"Dim" and "dim" both mean that the color or light is not bright or bright, but their usage is slightly different:

"Dim" refers to light, color, etc. Not bright or not bright usually means that the object that should be bright becomes dim or dim.

"Dim" is usually used to describe that the color or light is blocked or attenuated, losing its original brightness and brightness, often with dim, depressed and other negative emotional colors.

So the usage of the two is slightly different, but they both describe the situation that the color or light is not bright.