This is the 8879th most frequent Catalan word.
esvair
"Esvair" means "to fade" or "to vanish."
Here, 'esvair' is used reflexively in the context of something dispersing or vanishing, in this case, the fog.
La boira es va esvair quan va sortir el sol.
The fog dissipated when the sun came out.
In this sentence, 'esvair' conveys the notion of an abstract concept, such as doubt, disappearing or resolving.
El seu dubte es va esvair després de parlar amb l'expert.
Her doubt faded after talking to the expert.
Here, 'esvair' describes the literal act of erasing or making something vanish, in this case, ink.