This is the 12612th most frequent German word.
wellenreiten
Surfing.
Here, 'wellenreiten' is used as a verb ('to surf') in the infinitive form, describing the activity of surfing waves.
Ich liebe es, im Sommer wellenreiten zu gehen.
I love going surfing in the summer.
In this sentence, 'wellenreiten' is used as a noun ('surfing') to describe the specific activity.
Das Wellenreiten am Strand war gestern großartig.
Surfing at the beach yesterday was great.
Here, 'wellenreitens' is used as a genitive case form of the noun, indicating possession or relation to the art of surfing.