This is the 12374th most frequent Spanish word.
luminoso
Bright or luminous.
In this sentence, 'luminoso' describes the quality of the room having a lot of light, emphasizing its brightness.
La habitación es muy luminosa por las ventanas grandes.
The room is very bright due to the large windows.
Here, 'luminoso' is used to describe the sign emitting light, often artificially, making it easily visible.
Compré un cartel luminoso para la tienda.
I bought a luminous sign for the shop.
In this case, 'luminoso' metaphorically characterizes the smile with qualities of warmth and radiance, highlighting its emotional impact.