This is the 13910th most frequent German word.
flachen
The German word "flachen" means "to flatten" or "to level."
In this sentence, 'flachen' is used transitively to describe the action of making a surface even or flat.
Die Arbeiter flachen die unebene Oberfläche des Tisches mit Schleifpapier ab.
The workers flatten the uneven surface of the table with sandpaper.
Here, 'flachen' is used intransitively to indicate the gradual process of becoming even or flat, describing the terrain.
Nachdem das Gelände planiert wurde, begann es zu flachen.
After the terrain was leveled, it began to flatten out.
In this usage, 'flachen' conveys a continuous change toward a less uneven state, often involving natural landscapes.