This is the 1533rd most frequent German word.
dienen
"To serve"
In this sentence, 'dienen' means 'to serve a purpose' or 'to be used for'.
Dieses Gerät dient zur Messung der Temperatur.
This device is used to measure the temperature.
Here, 'dienen' denotes 'to serve' in the context of providing services to others.
Der Kellner dient den Gästen im Restaurant.
The waiter serves the guests in the restaurant.
In this example, 'dienen' implies 'to serve as' or 'to function as' in a given role.