This is the 6875th most frequent Dutch word.
aanzwelt
"Aanzwelt" means "swells up" or "rises gradually."
Here 'aanzwelt' is used as a verb to describe the action of increasing in size or volume, specifically referring to the water level of the river rising after rain.
De rivier aanzwelt na de hevige regen.
The river swells after the heavy rain.
In this sentence, 'aanzwelt' is applied metaphorically to describe the gradual growth or increase in confidence, not a physical but an emotional or psychological characteristic.
Zijn vertrouwen aanzwelt met elke behaalde overwinning.
His confidence swells with every victory achieved.
Here, 'aanzwelt' is describing the intensification or crescendo of music, showing its figurative use in an auditory context.