This is the 12549th most frequent German word.
wassen
"Wassen" is not a standard German word; it may be a misspelling or regional variation.
Here, 'waschen' refers to cleaning clothing using a washing machine or other methods involving water and detergent.
Er wollte seine Kleidung waschen, aber die Waschmaschine ist kaputt.
He wanted to wash his clothes, but the washing machine is broken.
Here, 'waschen' is used in its literal sense, meaning to clean something (in this case, hands) by applying water and possibly soap.
Ich muss meine Hände vor dem Essen waschen.
I need to wash my hands before eating.
In this sentence, 'waschen' describes the process of liquid (rain in this case) cleaning a surface (the car).