Mercury gets very bright sunlight as it is much closer to the sun than we are.
Dim
bright
it has bright
bright
Because of its distance from the Sun, it has dim sunlight.
Perhaps the part of the headlight bulb has burned out.
...would be dim.
Bright and dim are antonyms. Bright means having a high level of light or shining with intensity, while dim means having a low level of light or lacking brightness.
The word opposite to the word dim is bright.
Dim.
If you're talking about a gender difference, then the opposite is a bright girl. Otherwise the opposite of 'bright boy' is 'dull boy'