This is the 12441st most frequent Spanish word.
marciana
"Marciana" means "Martian" (female) or something related to the planet Mars.
Here, 'marciana' is used to describe a theme from Mars, giving an extraterrestrial or science-fiction context to the subject.
Esa película tiene una temática marciana e interesante.
That movie has a Martian and interesting theme.
In this case, 'marciana' metaphorically refers to unusual or bizarre ideas, implying they are as strange as something from Mars.
María siempre tiene ideas marcianas que nos sorprenden.
María always has outlandish ideas that surprise us.
Here, 'marciano' describes the resemblance of the landscape to the surface of the planet Mars, emphasizing its other-worldly appearance.