My colleague and friend in Zurich taught me the phrase Guten Rutsch:
It translates to “good slide,” and funny enough, it’s completely senseless. Derived from the Yiddish phrase “a git Rosch” (ראש השנה טוב), it means “a good beginning.” Most likely, that Yiddish phrase was jokingly translated to the similar-sounding “guten Rutsch.” Nowadays, the phrase is commonly understood as sliding into the new year.
May we all have a good slide into the new year!